@article {Simula.simula.1460,
	title = {Quantifying the Effect of Code Smells on Maintenance Effort},
	journal = {IEEE Transactions on Software Engineering},
	volume = {39},
	number = {8},
	year = {2012},
	pages = {1144-1156},
	abstract = {Context: Code smells are assumed to indicate bad design that leads to less maintainable code. However, this assumption has not been investigated in controlled studies with professional software developers. Aim: Our aim was to investigate the relationship between code smells and maintenance effort. Method: Six developers were hired to perform three maintenance tasks each on four functionally equivalent Java systems originally implemented by different companies. Each developer spent three to four weeks. In total, they modified 298 Java files in the four systems. An Eclipse IDE plug-in measured the exact amount of time a developer spent maintaining each file. A regression was used to explain the effort using file properties, including the number of smells. Results: None of the 12 investigated smells was significantly associated with increased effort after we adjusted for file size and the number of changes; Refused Bequest was significantly associated with decreased effort. File size and the number of changes explained most of the variation in effort. Conclusion: The effects of code smells on maintenance effort are limited. In general, to reduce maintenance effort, focusing on code size and the work practices that limit the number of changes may be more beneficial than refactoring code smells.},
	doi = {10.1109/TSE.2012.89},
	author = {Sj{\o}berg, Dag Ingar Kondrup and Yamashita, Aiko and Anda, Bente Cecilie Dahlum and Mockus, Audris and Dyb{\r a}, Tore}
}
@inbook {Simula.SE.643,
	title = {A Method to Measure Productivity Trends During Software Evolution},
	booktitle = {CCIS - Evaluation of Novel Approaches to Software Engineering},
	series = {Communications in Computer and Information Science},
	volume = {69},
	year = {2010},
	pages = {147-162},
	publisher = {Springer},
	organization = {Springer},
	chapter = {2},
	abstract = {Better measures of productivity are needed to support software process improvements. We propose and evaluate indicators of productivity trends that are based on the premise that productivity is closely related to the effort required to complete change tasks. Three indicators use change management data, while a fourth compares effort estimates of benchmarking tasks. We evaluated the indicators using data from 18 months of evolution in two commercial software projects. The productivity trend in the two projects had opposite directions according to the indicators. The evaluation showed that productivity trends can be quantified with little measurement overhead. We expect the methodology to be a step towards making quantitative self-assessment practices feasible even in low ceremony projects.},
	isbn = {978-3-642-14819-4},
	author = {Hans Christian {Benestad} and Anda, Bente Cecilie Dahlum and Arisholm, Erik},
	editor = {Leszek A. {Maciaszek} and Gonz{\textasciiacute}lez-P{\'e}rez, C{\'e}sar and Jablonski, Stefan}
}
@article {Simula.SE.301,
	title = {Understanding the Cost of Software Change: a Quantitative and Qualitative Investigation of Change Effort During Evolution of Two Software Systems},
	journal = {Empirical Software Engineering},
	volume = {15},
	number = {2},
	year = {2010},
	month = {April},
	pages = {166-203},
	abstract = {Making changes to software systems can prove costly and it remains a challenge to understand the factors that affect the costs of software evolution. This study sought to identify such factors by investigating the effort expended by developers to perform 336 change tasks in two different software organizations. We quantitatively analyzed data from version control systems and change trackers to identify factors that correlated with change effort. In-depth interviews with the developers about a subset of the change tasks further refined the analysis. Two central quantitative results found that volatility of requirements and dispersion of changed code consistently correlated with change effort. The analysis of the qualitative interviews pointed to two important, underlying cost drivers: Difficulties in anticipating side effects of changes and difficulties in comprehending dispersed code. This study demonstrates a novel method for combining qualitative and quantitative analysis to assess cost drivers of software evolution. Given our findings, we propose improvements to design practices and development tools to reduce the costs.},
	author = {Hans Christian {Benestad} and Anda, Bente Cecilie Dahlum and Arisholm, Erik}
}
@inproceedings {Simula.SE.323,
	title = {Are We More Productive Now? Analyzing Change Tasks to Assess Productivity Trends During Software Evolution},
	journal = {Evaluation of Novel Approaches to Software Engineering (ENASE)},
	year = {2009},
	publisher = {Elsevier},
	type = {Conference},
	abstract = {Organizations that maintain and evolve software would benefit from measuring productivity in an easy and reliable way. This could allow them to determine if new or improved practices are needed, and to evaluate improvement efforts. We propose and evaluate indicators of productivity trends that are based on the premise that productivity during software evolution is closely related to the effort required to complete change tasks. Three indicators use data about change tasks from change management systems, while a fourth compares effort estimates of benchmarking tasks. We evaluated the indicators using data from 18 months of evolution in two commercial software projects. The productivity trend in the two projects had opposite directions according to the indicators. Possible explanations were that one system became easier to maintain due to a large refactoring effort, while developers in the other project experienced less time pressure due to reduced use of fixed-price contracts. The evaluation of the indicators showed that productivity trends can be quantified with little measurement overhead. The methodology is a step towards making quantitative self-assessment practices feasible even in low ceremony projects.},
	isbn = {978-989811198-2},
	author = {Hans Christian {Benestad} and Anda, Bente Cecilie Dahlum and Arisholm, Erik},
	editor = {Jablonski, Stefan and Leszek A. {Maciaszek}}
}
@article {Simula.SE.307,
	title = {An Investigation of Use Case Quality in a Large Safety-Critical Software Development Project},
	journal = {Information and Software Technology},
	volume = {51},
	number = {Volume 51 Issue 12, December, 2009},
	year = {2009},
	pages = {1699-1711},
	publisher = {Elsevier},
	abstract = {Use case modeling is a much used technique for eliciting and documenting functional requirements. The quality of the use cases may have an important impact on the development project and on the resulting software product. This paper presents an empirical study of the changes that were made to the use case models of a large software project during the analysis phase. The results show which are the most difficult aspects of use case modeling in this project context, and show how the quality of the functional requirements, in particular correctness, completeness and clarity, was improved through the use case modeling process.},
	doi = {10.1016/j.infsof.2009.04.005},
	author = {Anda, Bente Cecilie Dahlum and Hansen, Kai and Sand, Gunhild}
}
@article {Simula.SE.196,
	title = {Understanding Software Maintenance and Evolution by Analyzing Individual Changes: a Literature Review},
	journal = {Journal of Software Maintenance and Evolution: Research and Practice},
	volume = {21},
	number = {6},
	year = {2009},
	pages = {349-378},
	author = {Hans Christian {Benestad} and Anda, Bente Cecilie Dahlum and Arisholm, Erik}
}
@inproceedings {Simula.SE.617,
	title = {Using Concept Mapping for Maintainability Assessments},
	journal = {3rd IEEE International Symposium on Empirical Software Engineering and Measurement (ESEM)},
	year = {2009},
	month = {October 2009},
	publisher = {IEEE},
	type = {Conference},
	abstract = {Many important phenomena within software engineering are difficult to define and measure. A good example is software maintainability, which has been the subject of considerable research and is believed to be a critical determinant of total software costs. Yet, there is no common agreement on how to describe and measure software maintainability in a concrete setting. We propose using concept mapping, a well-grounded method used in social research, to operationalize this concept according to a given goal and perspective. We apply this method to describe four systems that were developed as part of an industrial multiple-case study. The outcome is a conceptual map that displays an arrangement of maintainability constructs, their interrelations and corresponding measures. Our experience is that concept mapping (1) provides a structured way of combining static code analysis and expert judgment; (2) helps tailoring the choice of measures to a particular system context; and (3) supports the mapping between software measures and aspects of software maintainability. As such, it represents a strong addition to existing frameworks for evaluating quality such as ISO/IEC 9126 and GQM, and tools for static measurement of software code. Overall, we find that concept mapping provides a systematic, structured and repeatable method for developing constructs and measures of the phenomenon of interest, and we deem it useful for defining constructs and measures of other aspects of software engineering, in addition to maintainability.},
	isbn = {10.1109/ESEM.2009.5316044},
	author = {Yamashita, Aiko and Anda, Bente Cecilie Dahlum and Sj{\o}berg, Dag Ingar Kondrup and Hans Christian {Benestad} and Per Einar {Arnstad} and Moonen, Leon},
	editor = {Miller, James and Selby, Rick}
}
@article {Simula.SE.195,
	title = {Variability and Reproducibility in Software Engineering: a Study of Four Companies That Developed the Same System},
	journal = {IEEE Transactions on Software Engineering},
	volume = {35},
	number = {3},
	year = {2009},
	pages = {407-429},
	publisher = {IEEE},
	abstract = {The scientific study of a phenomenon requires it to be reproducible. Mature engineering industries are recognized by projects and products that are, to some extent, reproducible. However, reproducibility in software engineering (SE) has not been thoroughly investigated, although generalizing the results of SE studies depend on SE phenomena being reproducible. We report a longitudinal multiple-case study of variations and reproducibility in software development, from bidding to deployment, on the basis of the same requirements specification. In a call for tender to 81 consultancy companies, 35 responded. Four of them developed the system independently. The firm price, planned schedule, and planned development process, had, respectively, \&ldquo;low\&rdquo;, \&ldquo;low\&rdquo;, and \&ldquo;medium\&rdquo; reproducibility. The contractor\&$\#$39;s internal costs, actual lead time, and schedule overrun of the projects had, respectively, \&ldquo;medium\&rdquo;, \&ldquo;high\&rdquo;, and \&ldquo;low\&rdquo; reproducibility. The quality dimensions of the delivered products, reliability, usability, and maintainability had, respectively, \&ldquo;low\&rdquo;, \&ldquo;high\&rdquo;, and \&ldquo;low\&rdquo; reproducibility. We proposed a coarse-grained model that uses software process inputs to predict key project outcomes. The comparisons of the model\&$\#$39;s predictions with the actual outcomes indicate some reproducibility. This initial work may contribute to developing more accurate models, but making SE more reproducible remains a great challenge for SE research, education, and industry.},
	doi = {10.1109/TSE.2008.89 },
	author = {Anda, Bente Cecilie Dahlum and Sj{\o}berg, Dag Ingar Kondrup and Mockus, Audris}
}
@inbook {Sjoberg.2007.1,
	title = {Building Theories in Software Engineering},
	booktitle = {Advanced Topics in Empirical Software Engineering},
	year = {2008},
	pages = {312-336},
	publisher = {Springer},
	organization = {Springer},
	chapter = {12},
	abstract = {Empirical studies have become an integral element of software engineering research and practice. This unique text/reference includes chapters from some of the top international empirical software engineering researchers and focuses on the practical knowledge necessary for conducting, reporting and using empirical methods in software engineering.},
	author = {Sj{\o}berg, Dag Ingar Kondrup and Dyb{\r a}, Tore and Anda, Bente Cecilie Dahlum and Jo Erskine {Hannay}},
	editor = {Shull, Forrest and Singer, Janice and Sj{\o}berg, Dag Ingar Kondrup}
}
@inproceedings {Simula.SE.275,
	title = {Flexibility in Research Designs in Empirical Software Engineering},
	journal = {Evaluation and Assessment in Software Engineering (EASE 2008)},
	year = {2008},
	publisher = {BCS},
	type = {Conference},
	abstract = {Problem outline:A common way of classifying empirical research designs is in qualitative and quantitative designs. Typically, particular research methods (e.g., case studies, action research, experiments and surveys) are associated to one or the other of these designs. Studies in empirical software engineering (ESE) are often exploratory and often involve software developers and development organizations. As a consequence, it may be difficult to pre-plan all aspects of the studies, and to be successful, ESE studies must often be designed to handle upcoming changes during the conduct of the study. A problem with the above classification is that it does not cater for the flexibility in the design. Position: This paper suggests viewing research in ESE along the axis of flexible and fixed designs, which is both orthogonal to the axis of quantitative and qualitative designs, and independent of the particular research method. According to the traditional view of ESE, changes to the research design in the course of a study are typically regarded as threats to the validity of the study results. However, by viewing the study designs as flexible, practical challenges can be turned to useful information. The validity of the results of studies with flexible research designs can be established by applying techniques that are traditionally used for qualitative designs. This paper urges for increased recognition of flexible designs in ESE and discusses techniques for establishing the trustworthiness in flexible designs.},
	author = {Vigdis By {Kampenes} and Anda, Bente Cecilie Dahlum and Dyb{\r a}, Tore},
	editor = {Giuseppe Visaggio M {Turner}}
}
@techreport {Simula.SE.317,
	title = {An Investigation of Change Effort in Two Evolving Software Systems},
	year = {2008},
	publisher = {Simula Research Laboratory},
	author = {Hans Christian {Benestad} and Anda, Bente Cecilie Dahlum and Arisholm, Erik}
}
@book {Simula.SE.295,
	title = {Proceedings of the First Workshop on Empirical Studies of Model-Driven Engineering (ESMDE)},
	volume = {392},
	year = {2008},
	note = {http://CEUR-WS.org/Vol-392},
	publisher = {CEUR},
	abstract = {It is often difficult to rigorously evaluate Model-Driven Engineering (MDE) technologies. Performing empirical studies require skills, experience and tacit knowledge that are in many ways very different from the {\textquotedblleft}core{\textquotedblright} MDE research. Furthermore, empirical studies often entail large investments in terms of human resources, time and money. Nevertheless, evaluations of MDE technologies are needed in order to demonstrate the soundness, applicability, and cost effectiveness of proposed technologies in various development contexts. The aim of this workshop is to exemplify and discuss ways in which proposed modeldriven engineering (MDE) technologies should be evaluated, with a specific emphasis on how to plan, conduct, analyze and report the results of empirical studies. The workshop will have focus on the challenges of empirical studies involving human users, since MDE technologies are typically expected to be used by software engineers to improve various quality aspects of software systems and the productivity of software development. More detailed topics include: What are the main obstacles and potential remedies when performing empirical studies of MDE? What are the main threats to validity of empirical studies of MDE, and how should they be dealt with? For example, since MDE often represent new and complex technology, the selection and training of human subjects who participate in empirical studies often become critical factors. What are the most important outcome variables of the costs and benefits of MDE? How can quality be measured in the context of MDE? And can we define an unambiguous set of (benchmark) outcome measures to facilitate metaanalyses across subjects, systems, tasks and technologies? The goal of the workshop is to pave the way for the development of a MDE-specific framework for empirical evaluation of MDE technologies, or at least provide a minimum standard for evaluation that published work in the MDE community should abide by.},
	author = {Arisholm, Erik and Briand, Lionel and Anda, Bente Cecilie Dahlum}
}
@techreport {Simula.SE.297,
	title = {A Systematic Review of Empirical Software Engineering Studies That Analyze Individual Changes},
	number = {2008-05},
	year = {2008},
	month = {September},
	publisher = {Simula Research Laboratory},
	author = {Hans Christian {Benestad} and Anda, Bente Cecilie Dahlum and Arisholm, Erik}
}
@article {Simula.SE.197,
	title = {Usability Inspection: a Comparative Study of the Evaluator Performance of Work-Domain Experts Vs. Usability Experts},
	journal = {journal},
	year = {2008},
	abstract = {When applications that are tailored to work domains of which usability experts have little knowledge are evaluated, the usefulness of usability inspection methods is challenged. To counter this challenge, usability inspections with work-domain experts have been explored, but no empirical research has been reported on such experts{\textquoteright} performance as evaluators. The present study compares the performance of work-domain experts and usability experts, with respect to the validity and thoroughness of their evaluations. Fifteen work-domain experts and 12 usability experts participated. The applied inspection method was group-based expert walkthrough. The basis for comparison was user test results. The work-domain experts produced equally valid but less thorough evaluation results than the usability experts. On average, two work-domain experts produced results of similar quality to those of one usability expert, which implies that work-domain experts may substitute for usability experts if the number of evaluators is increased. These results should be taken into account when developing future usability inspection methods with work-domain experts as evaluators.},
	author = {F{\o}lstad, Asbj{\o}rn and Anda, Bente Cecilie Dahlum and Sj{\o}berg, Dag Ingar Kondrup}
}
@inproceedings {Simula.SE.123,
	title = {Assessing Software System Maintainability Using Structural Measures and Expert Assessments},
	journal = {the 23rd International Conference on Software Maintenance (ICSM 2007, the paper received Best Paper Award)},
	year = {2007},
	month = {October},
	pages = {204-213},
	publisher = {IEEE},
	type = {Conference},
	abstract = {A software client usually has few means of assessing the maintainability of a software system in the acquisition process. Software maintenance is often expensive, hence, strategies for assessing the maintainability of complete software systems are important. Assessing the maintainability of complete systems is difficult due to the influence of many different factors such as the people, tasks and tools, in addition to the code. Most research on maintainability focuses on individual classes of individual systems. This paper describes an empirical study where the maintainability of four functionally equivalent systems was assessed using both structural measures and expert assessments. The results suggest that such a combination may be useful. Although, the assessment based on structural measures mostly corresponded with the expert assessments, there were several examples of potential maintainability problems that were not captured by the structural measures.},
	isbn = {1-4244-1256-0},
	author = {Anda, Bente Cecilie Dahlum},
	editor = {Canfora, Gerardo and Tahvildari, Ladan}
}
@inproceedings {Simula.SE.141,
	title = {Assessment of Software System Evolvability},
	journal = {International Workshop on Principles of Software Evolution (IWPSE 2007)},
	year = {2007},
	pages = {71-74},
	publisher = {ACM},
	type = {Workshop},
	abstract = {The evolvability, the ease of further development, of a software systems is difficult to assess, but may have large economic consequences. Many studies have investigated the relations between particular software metrics and effort on evolving individual classes, but little attention has been given to methods for assessing and measuring evolvability of complete software systems. This paper discusses such methods, and motivates that they should use a combination of structural code measures and expert assessments. This is exemplified in a case study assessing the evolvability of four functionally equivalent systems. The paper also gives with directions for future work on evolvability assessments.},
	isbn = {978-1-59593-811-4},
	author = {Anda, Bente Cecilie Dahlum},
	editor = {Di Penta, Massimiliano and Lanza, Michele}
}
@inproceedings {Benestad.2006.1,
	title = {Assessing Software Product Maintainability Based on Class-Level Structural Measures},
	journal = {7th International Conference on Product-focused Software Process Improvement (PROFES)},
	year = {2006},
	pages = {94-111},
	publisher = {Springer-Verlag},
	type = {Conference},
	abstract = {A number of structural measures have been suggested to support the assessment and prediction of software quality attributes. The aim of our study is to investigate how class-level measures of structural properties can be used to assess the maintainability of a software product as a whole. We survey, structure and discuss current practices on this topic, and apply alternative strategies on four functionally equivalent systems that were constructed as part of a multi-case study. In the absence of historical data needed to build statistically based prediction models, we apply elements of judgment in the assessment. We show how triangulation of alternative strategies as well as sensitivity analysis may increase the confidence in assessments that contain elements of judgment. This paper contributes to more systematic practices in the application of structural measures. Further research is needed to evaluate and improve the accuracy and precision of judgment-based strategies.},
	isbn = {0302-9743},
	author = {Hans Christian {Benestad} and Anda, Bente Cecilie Dahlum and Arisholm, Erik},
	editor = {M{\"u}nch, J{\"u}rgen}
}
@inproceedings {Anda.2006.1,
	title = {A Case Study on the Application of UML in Legacy Development},
	journal = {ISESE{\textquoteright}2006 (Fifth ACM-IEEE International Symposium on Empirical Software Engineering)},
	year = {2006},
	month = {September},
	pages = {124-133},
	publisher = {ACM Press, Rio de Janiero, Brasil, September 21-22},
	type = {Conference},
	abstract = {Model-driven development with UML is becoming a de facto standard in industry, but although much of today{\textquoteright}s software development is about enhancing existing systems, there is no well-defined process for model-driven development in the context of legacy systems. To ensure the relevance of research on model-driven development with UML, there is a need for studies of actual use of UML in software development companies. As part of a software process initiative, we conducted a case study in a large development project where some of the development teams enhanced existing components, while other teams developed software from scratch. The results from this case study showed that those who applied UML in modelling and enhancing legacy software experienced more challenges and fewer benefits from the use of UML than did the developers who modelled and developed new software. Overall our results show a need for better methodological support on applying UML in legacy development.},
	isbn = {1-59593-218-6},
	author = {Anda, Bente Cecilie Dahlum and Hansen, Kai},
	editor = {Claes Wohlin Jos {Maldonado}}
}
@inbook {Anda.2006.2,
	title = {Experiences From Introducing UML-Based Development in a Large Safety-Critical Project},
	booktitle = {Software Process Improvement. Results and Experiences from the Field},
	year = {2006},
	pages = {329-359},
	publisher = {Springer},
	organization = {Springer},
	chapter = {18},
	isbn = {3-540-32178-0},
	author = {Anda, Bente Cecilie Dahlum and Hansen, Kai and Gullesen, Ingolf and Hanne Kristin {Thorsen}},
	editor = {Conradi, Reidar and Dyb{\r a}, Tore and Sj{\o}berg, Dag Ingar Kondrup and Ulsund, Tor}
}
@article {Anda.2006.3,
	title = {Experiences From Using a UML-Based Development Method in a Large Safety-Critical Project},
	journal = {Empirical Software Engineering},
	volume = {11},
	number = {4},
	year = {2006},
	month = {December},
	pages = {555-581},
	author = {Anda, Bente Cecilie Dahlum and Hansen, Kai and Gullesen, Ingolf and Hanne Kristin {Thorsen}}
}
@inproceedings {Holt.2006.2,
	title = {Experiences With Precise State Modeling in an Industrial Safety Critical System},
	journal = {Critical Systems Development Using Modeling Lanuguages, CSDUML{\textquoteright}06},
	year = {2006},
	month = {October},
	pages = {68-77},
	publisher = {Springer},
	type = {Workshop},
	edition = {9th edition},
	chapter = {6},
	abstract = {The development of safety critical systems is a complex and challenging task. There are many claims regarding how precise modeling, either with the UML or other modeling notations, can yield benefits in terms of more rigorous specifications and designs. This paper reports on experiences from applying statechart-driven UML modeling in the development of a safety-critical system at ABB. The primary lessons learned from the study are related to the impact of precise modeling on the ease of transitioning to design.},
	author = {Nina Elisabeth {Holt} and Anda, Bente Cecilie Dahlum and Asskildt, Knut and Briand, Lionel and Endresen, Jan and Fr{\o}ystein, Sverre},
	editor = {Siv Hilde {Houmb} and Georg, Geri and France, Robert and Dorina C. {Petriu} and J{\"u}rjens, Jan}
}
@article {Karahasanovic.2005.2,
	title = {Collecting Feedback During Software Engineering Experiments},
	journal = {Empirical Software Engineering},
	volume = {10},
	number = {2},
	year = {2005},
	pages = {113-147},
	abstract = {Objective: To improve the qualitative data obtained from software engineering experiments by gathering feedback during experiments. Rationale: Existing techniques for collecting quantitative and qualitative data from software engineering experiments do not provide sufficient information to validate or explain all our results. Therefore, we would like a cost-effective and unobtrusive method of collecting feedback from subjects during an experiment to augment other sources of data. Design of study: We formulated a set of qualitative questions that might be answered by collecting feedback during software engineering experiments. We then developed a tool to collect such feedback from experimental subjects. This feedback-collection tool was used in four different experiments and we evaluated the usefulness of the feedback obtained in the context of each experiment. The feedback data was triangulated with other sources of quantitative and qualitative data collected for the experiments. Results: We have demonstrated that the collection of feedback during experiments provides useful additional data to: validate the data obtained from other sources about solution times and quality of solutions; check process conformance; understand problem solving processes; identify problems with experiments; and understand subjects{\textquoteright} perception of experiments. Conclusions: Feedback collection has proved useful in four experiments and we intend to use the feedback-collection tool in a range of other experiments to further explore the cost-effectiveness and limitations of this technique. It is also necessary to carry out a systematic study to more fully understand the impact of the feedback-collecting tool on subjects{\textquoteright} performance in experiments.},
	author = {Karahasanovic, Amela and Anda, Bente Cecilie Dahlum and Arisholm, Erik and Siw Elisabeth {Hove} and J{\o}rgensen, Magne and Sj{\o}berg, Dag Ingar Kondrup and Welland, Ray}
}
@inproceedings {Mohagheghi.2005.1,
	title = {Effort Estimation of Use Cases for Incremental Large-Scale Software Development},
	journal = {ICSE{\textquoteright}05},
	year = {2005},
	month = {May},
	pages = {303-311},
	publisher = {The 27th International Conference on Software Engineering, 15-21 May, St Louis, Missouri, USA},
	type = {Conference},
	abstract = {This paper describes an industrial study of an effort estimation method based on use cases, the Use Case Points method. The original method was adapted to incremental development and evaluated on a large industrial system with modification of software from the previous release. We modified the following elements of the original method: a) complexity assessment of actors and use cases, and b) the handling of non-functional requirements and team factors that may affect effort. For incremental development, we added two elements to the method: c) counting both all and the modified actors and transactions of use cases, and d) effort estimation for secondary changes of software not reflected in use cases. We finally extended the method to: e) cover all development effort in a very large project. The method was calibrated using data from one release and it produced an estimate for the successive release that was only 17\% lower than the actual effort. The study identified factors affecting effort on large projects with incremental development. It also showed how these factors can be calibrated for a specific context and produce relatively accurate estimates.},
	author = {Mohagheghi, Parastoo and Anda, Bente Cecilie Dahlum and Conradi, Reidar},
	editor = {Mohagheghi, Parastoo and Anda, Bente Cecilie Dahlum and Conradi, Reidar}
}
@inproceedings {Hove.2005.1,
	title = {Experiences From Conducting Semi-Structured Interviews in Empirical Software Engineering Research},
	journal = {11th IEEE International Software Metrics Symposium (METRICS 2005), 19-22 September, Como, Italy},
	year = {2005},
	month = {September, 2005},
	pages = {23(1-10)},
	publisher = {IEEE},
	type = {Conference},
	abstract = {Many phenomena related to software development are qualitative in nature. Relevant measures of such phenomena are often collected using semi-structured interviews. Such interviews involve high costs, and the quality of the collected data is related to how the interviews are conducted. Careful planning and conducting of the interviews are therefore necessary, and experiences from interview studies in software engineering should consequently be collected and analyzed to provide advice to other researchers. We have brought together experiences from 12 software engineering studies, in which a total of 280 interviews were conducted. Four areas were particularly challenging when planning and conducting these interviews; estimating the necessary effort, ensuring that the interviewer had the needed skills, ensuring good interaction between interviewer and interviewees, and using the appropriate tools and project artifacts. The paper gives advice on how to handle these areas and suggests what information about the interviews should be included when reporting studies where interviews have been used in data collection. Knowledge from other disciplines is included. By sharing experience, knowledge about the accomplishments of software engineering interviews is increased and hence, measures of high quality can be achieved.},
	isbn = {0-7695-2371-4},
	author = {Siw Elisabeth {Hove} and Anda, Bente Cecilie Dahlum},
	editor = {Hove, Anda}
}
@techreport {25347,
	title = {Experiences From Using a UML-Based Development Method in a Large Safety-Critical Project},
	year = {2005},
	note = {This technical report is an earlier version of a published book chapter. The published version can be found here:https://www.simula.no/publications/experiences-introducing-uml-based-development-large-safety-critical-project},
	publisher = {Simula Research Laboratory},
	author = {Anda, Bente Cecilie Dahlum and Hansen, Kai and Gullesen, Ingolf and Hanne Kristin {Thorsen}}
}
@inproceedings {Hansen.2005.5,
	title = {Experiences With a UML-Based Development Method for SIL Products},
	journal = {CSDUML 2005, The 4th International Workshop on Critical Systems Development Using Modeling Languages, 27th September, Fredrikstad, Norway},
	year = {2005},
	pages = {87-95},
	publisher = {Technical report, Institut f{\"u}r Informatik, Technische Universit{\"a}t M{\"u}nchen},
	type = {Workshop},
	abstract = {This article describes the results of an investigation into the suitability of methodology based on UML in an IEC 61508 development project that developed SIL products. Feedback was gathered from project members through interviews and questionnaires. The results show that the method led to improvements in some aspects of the development process that are particularly important in the development of SIL products. These improvements were related to documentation, traceability from requirements to code, and the quality of the code. The results also show, however, that the opinions of the project members differed a lot, and consequently that it is difficult to define one method with which a large number of developers with different backgrounds and mind sets will be content.},
	author = {Hansen, Kai and Anda, Bente Cecilie Dahlum and Gullesen, Ingolf},
	editor = {Siv Hilde {Houmb} and J{\"u}rjens, Jan and France, Robert}
}
@article {Anda.2005.2,
	title = {Investigating the Role of Use Cases in the Construction of Class Diagrams},
	journal = {Empirical Software Engineering},
	volume = {10},
	number = {3},
	year = {2005},
	month = {July},
	pages = {285-309},
	abstract = {Several approaches have been proposed for the transition from functional requirements to object-oriented design. In a use case-driven development process, the use cases are important input to the identification of classes and their methods. There is, however, no established, empirically validated technique for the transition from use cases to class diagrams. One recommended technique is to derive classes by analyzing the use cases. It has, nevertheless, been reported that this technique leads to problems, such as the developers missing requirements and mistaking requirements for design. An alternative technique is to identify classes from a textual requirements specification and subsequently apply the use case model to validate the resulting class diagram. This paper describes two controlled experiments conducted to investigate these two approaches to applying a use case model in an object-oriented design process. The first experiment was conducted with 53 students as subjects. Half of the subjects used a professional modelling tool; the other half used pen and paper. The second experiment was conducted with 22 professional software developers as subjects, all of whom used one of several modelling tools. The first experiment showed that applying use cases to validate class diagrams constructed from textual requirements led to more complete class diagrams than did the derivation of classes from a use case model. In the second experiment, however, we found no such difference between the two techniques. In both experiments, deriving class diagrams from the use cases led to a better structure of the class diagrams. The results of the experiments therefore show that the technique chosen for the transition from use cases to class diagrams affect the quality of the class diagrams, but also that the effects of the techniques depend on the categories of developer applying it and on the tool with which the technique is applied.},
	author = {Anda, Bente Cecilie Dahlum and Sj{\o}berg, Dag Ingar Kondrup}
}
@inproceedings {Anda.2005.6,
	title = {A Multiple-Case Study of Effort Estimation Based on Use Case Points},
	journal = {ISESE{\textquoteright}2005 (Fourth International Symposium on Empirical Software Engineering)},
	year = {2005},
	pages = {407-416},
	publisher = {IEEE Computer Society, Noosa, Australia, November 17-18},
	type = {1},
	abstract = {There is much interest in industry for the estimation of software development effort based on use cases, but little scientific evaluation of applying use cases in estimation has been reported. We investigated one particular method, the use case points method, in a multiple-case study. The Software Engineering Department at Simula issued a tender for a system, and 35 companies responded, with estimates ranging from 78 to 654 hours. We chose four companies to develop the system. They all implemented the same functionality, but their development processes varied, ranging from a light, mainly code-and-fix process, to a heavy process with much emphasis on analysis and design. The use case points method estimated this project to 430 hours. This was equal to the actual effort spent on implementing the system by the company with the lightest development process. In our opinion, the results from this study may represent a basis for measuring size of the use cases and choosing productivity factor (hours per use case point) when estimating based on use cases. The three other companies spent 587, 829 and 943 hours respectively, showing that a heavier development process and more emphasis on non-functional requirements may increase effort by more than 100\%.},
	author = {Anda, Bente Cecilie Dahlum and Hans Christian {Benestad} and Siw Elisabeth {Hove}}
}
@inproceedings {SE.5.Anda.2003,
	title = {Applying Use Cases to Design Versus Validate Class Diagrams - a Controlled Experiment Using a Professional Modelling Tool},
	journal = {ISESE{\textquoteright}2003 (Second International Symposium on Empirical Software Engineering)},
	year = {2003},
	month = {September 30 - October 1},
	pages = {50-60},
	publisher = {IEEE Computer Society},
	type = {Conference},
	address = {Rome, Italy},
	abstract = {Several processes have been proposed for the transition from functional requirements to an object-oriented design, but these processes have been subject to little empirical validation. A use case driven development process is often recommended when applying UML. Nevertheless, it has been reported that this process leads to problems, such as the developers missing some requirements and mistaking requirements for design. This paper describes a controlled experiment, with 53 students as subjects, conducted to investigate two alternative processes for applying a use case model in an object-oriented design process. One process was use case driven, while the other was a responsibility-driven process in which the use case model was applied as a means of validating the resulting class diagram. Half of the subjects used the modelling tool Tau UML Suite from Telelogic; the other half used pen and paper. The results show that the validation process led to class diagrams implementing more of the requirements. The use case driven process did, however, result in class diagrams with a better structure. The results also show that those who used the modelling tool spent more time on constructing class diagrams than did those who used pen and paper. We experienced that it requires much more effort to organize an experiment with a professional modelling tool than with only pen and paper.},
	isbn = {not found},
	author = {Anda, Bente Cecilie Dahlum and Sj{\o}berg, Dag Ingar Kondrup},
	editor = {found, not}
}
@inbook {Sjoberg.2003.1,
	title = {Challenges and Recommendations When Increasing the Realism of Controlled Software Engineering Experiments},
	booktitle = {Empirical Methods and Studies in Software Engineering: Experiences from ESERNET},
	series = {Lecture Notes in Computer Science, Volume 2765},
	year = {2003},
	pages = {24-38},
	publisher = {Springer},
	organization = {Springer},
	chapter = {Part II: Method Chapters},
	address = {Berlin / Heidelberg},
	abstract = {An important goal of most empirical software engineering experiments is the transfer of the research results to industrial applications. To convince industry about the validity and applicability of the results of controlled software engineering experiments, the tasks, subjects and the environments should be as realistic as practically possible. Such experiments are, however, more demanding and expensive than experiments involving students, small tasks and pen-and-paper environments. This chapter describes challenges of increasing the realism of controlled experiments and lessons learned from the experiments that have been conducted at Simula Research Laboratory.},
	isbn = {978-3-540-40672-3},
	author = {Sj{\o}berg, Dag Ingar Kondrup and Anda, Bente Cecilie Dahlum and Arisholm, Erik and Dyb{\r a}, Tore and J{\o}rgensen, Magne and Karahasanovic, Amela and Vok{\'a}c, Marek},
	editor = {Conradi, Reidar and Alf Inge {Wang}}
}
@phdthesis {SE.3.Anda.2003,
	title = {Empirical Studies of Construction and Application of Use Case Models},
	year = {2003},
	note = {ISSN 1501-7710, Nr. 268},
	month = {March},
	school = {University of Oslo},
	type = {phd},
	abstract = {Requirements engineering is a critical part of the development of software systems. A plethora of techniques has been proposed to elicit and document the requirements of a software system. One technique that is now widely used in industry is use case modelling. Although the technique imposes no particular constraints on the methodology used in other phases in a development project, it is most frequently used in combination with object-oriented development. In addition to serving as a requirements capture vehicle and a means for developers to communicate with end users and customers, use cases are claimed to be useful for estimating software development effort and for facilitating the transition from functional requirements to software design. Despite the important role of use case modelling in software development projects, and the numerous recommendations and claims that have been made about how to construct and apply use case models, there are very few systematic empirical studies in this field. This thesis investigates the use case modelling process and the role of use cases in software development projects by means of a number of empirical studies. In total, five experiments with 37 professional software developers and approximately 250 students as subjects, three industrial case studies and 11 interviews with project managers and senior developers were conducted. The empirical studies were conducted on the construction of use case models by the use of guidelines and inspections, and the application of use case models in (a) the estimation of software development effort and (b) the design of object-oriented systems. The results indicate that guidelines based on templates support the construction of use case models that are of higher quality, and that are easier to understand for the readers, than guidelines without specific details on how to document use cases. The results also indicate that quality may be further enhanced by combining the template guidelines with style guidelines for the documentation of the flow of events of each use case. A taxonomy of defects in use case models, and a checklist-based inspection technique to detect such defects, were proposed. The evaluation of this technique shows that it may increase the detection of serious defects in a use case model and also that there is a large difference between the defects detected by the developers of the use case model and by the end-users of the resulting system. The results further demonstrate that use case models can be used successfully to (a) estimate software development effort, (b) identify the prerequisites for successful use and (c) propose a refined and potentially improved version of an existing method for use case based estimation, the use case points method. The results also indicate that the quality of a design model is affected by the way in which a use case model is applied in an object-oriented design process, in particular, that a process which applies a use case model in validation results in class diagrams that implement more of the requirements, while a use case driven process results in class diagrams with a better structure. The empirical studies were exploratory because few similar studies have been conducted. Among other things, they required the development of original experimental designs. The major contribution of this thesis is, therefore, that it represents a starting point for more thorough empirical evaluation in the area of use case modelling},
	author = {Anda, Bente Cecilie Dahlum}
}
@inproceedings {SE.5.Syversen.2003,
	title = {An Evaluation of Applying Use Cases to Construct Design Versus Validate Design},
	journal = {Hawaii International Conference on System Sciences (HICSS-36)},
	year = {2003},
	month = {January 6-9},
	publisher = {-},
	type = {1},
	address = {Big Island, Hawaii},
	abstract = {Use case models capture and describe the functional requirements of a software system. A use case driven development process, where a use case model is the principal basis for constructing an object-oriented design, is recommended when applying UML. There are, however, some problems with use case driven development processes and alternative ways of applying a use case model have been proposed. One alternative is to apply the use case model in a responsibility-driven process as a means to validate the design model. We wish to study how a use case model best can be applied in an object-oriented development process and have conducted a pilot experiment with 26 students as subjects to compare a use case driven process against a responsibility-driven process in which a use case model is applied to validate the design model. Each subject was given detailed guidelines on one of the two processes, and used those to construct design models consisting of class and sequence diagrams. The resulting class diagrams were evaluated with regards to realism, that is, how well they satisfied the requirements, size and number of errors. The results show that the validation process produced more realistic class diagrams, but with a larger variation in the number of classes. This indicates that the use case driven process gave more, but not always more appropriate, guidance on how to construct a class diagram The experiences from this pilot experiment were also used to improve the experimental design, and the design of a follow-up experiment is presented.},
	isbn = {0-7695-1874-5},
	author = {Syversen, E. and Anda, Bente Cecilie Dahlum and Sj{\o}berg, Dag Ingar Kondrup},
	editor = {Dennis, Eileen}
}
@techreport {Karahasanovic.2003.3,
	title = {A Think-Aloud Support Tool for Collecting Feedback in Large-Scale Software Engineering Experiments},
	number = {2003-7},
	year = {2003},
	publisher = {Simula Research Laboratory},
	abstract = {The think-aloud method has proven useful for studying how a technology is used. However, it is labour-intensive and makes demands on resources for studies with many subjects. This paper describes a tool, called the think-aloud tool, that we have developed to support the collection of feedback from subjects in large-scale software engineering experiments. This tool instructs the subjects, at regular intervals, to write down their thoughts on a web-based screen and collects their feedback. An empirical evaluation of this tool is reported. The results from four controlled experiments suggest that the think-aloud tool is a valuable means for increasing the quality of large-scale software engineering experiments. The results also indicate that the participants were mostly positive to the tool and had no significant problems in verbalising their thoughts. The tool we proposed adds to an available set of tools for data collection in software engineering experiments. Whereas we have experience with the think-aloud tool in software engineering experiments, there is also potential for using such a tool in other areas in which the think-aloud method is used in studies involving a computer system.},
	author = {Karahasanovic, Amela and Anda, Bente Cecilie Dahlum and Arisholm, Erik and Siw Elisabeth {Hove} and J{\o}rgensen, Magne and Sj{\o}berg, Dag Ingar Kondrup}
}
@inproceedings {SE.5.Anda.2002.a,
	title = {Comparing Effort Estimates Based on Use Case Points With Expert Estimates},
	journal = {Empirical Assessment in Software Engineering (EASE)},
	year = {2002},
	month = {April 8-10},
	type = {Conference},
	address = {Keele, UK},
	abstract = {Use case models are used in object-oriented analysis for capturing and describing the functional requirements of a system. Attributes of a use case model may therefore serve as measures of the size and complexity of the functionality of a system. Many organizations use a system\&$\#$39;s use case model in the estimation process. This paper reports the results from a study conducted to evaluate a method for estimating software development effort based on use cases, the use case points method, by comparing it with expert estimates. A system was described by a brief problem statement and a detailed use case model. The use case points method gave an estimate that was closer to the actual effort spent on implementing the system than most estimates made by 37 experienced professional software developers divided into 11 groups (MRE of 0.21 versus MMRE of 0.37). The results support existing claims that the use case points method may be used successfully in estimating software development effort. They also show that the combination of expert estimates and method based estimates may be particularly beneficial when the estimators lack specific experience with the application domain and the technology to be used.},
	author = {Anda, Bente Cecilie Dahlum}
}
@inproceedings {SE.5.Sjoeberg.2002,
	title = {Conducting Realistic Experiments in Software Engineering},
	journal = {ISESE{\textquoteright}2002 (First International Symposium on Empirical Software Engineering)},
	year = {2002},
	month = {October 3-4},
	pages = {17-26},
	publisher = {IEEE Computer Society},
	type = {1},
	abstract = {An important goal of most empirical software engineering research is the transfer of research results to industrial applications. Two important obstacles for this transfer are the lack of control of variables of case studies, i.e., the lack of explanatory power, and the lack of realism of controlled experiments. While it may be difficult to increase the explanatory power of case studies, there is a large potential for increasing the realism of controlled software engineering experiments. To convince industry about the validity and applicability of the experimental results, the tasks, subjects and the environments of the experiments should be as realistic as practically possible. Such experiments are, however, more expensive than experiments involving students, small tasks and pen-and-paper environments. Consequently, a change towards more realistic experiments requires a change in the amount of resources spent on software engineering experiments. This paper argues that software engineering researchers should apply for resources enabling expensive and realistic software engineering experiments similar to how other researchers apply for resources for expensive software and hardware that are necessary for their research. The paper describes some of the experiences from recent experiments that varied in size from involving one software professional for 5 days to 130 software professionals, from 9 consultancy companies, for one day each.},
	isbn = {0-7695-1796-X},
	author = {Sj{\o}berg, Dag Ingar Kondrup and Anda, Bente Cecilie Dahlum and Arisholm, Erik and Dyb{\r a}, Tore and J{\o}rgensen, Magne and Karahasanovic, Amela and Koren, E. and Vok{\'a}c, Marek},
	editor = {found, not}
}
@inproceedings {SE.5.Anda.2002.c,
	title = {Improving Estimation Practices by Applying Use Case Models},
	journal = {4th International Conference on Product Focused Software Process Improvement},
	year = {2002},
	month = {December 9 - 11},
	pages = {383-397},
	publisher = {Springer-Verlag},
	type = {Conference},
	address = {Rovaniemi, Finland},
	abstract = {An estimation method based on use cases, the use case points method, has given promising results. However, more knowledge is needed about the contexts in which the method can be applied and how it should be adapted to local environments to improve the estimation process. We applied the use case points method to several projects in a Scandinavian software development company as the first activity in a software process improvement project on improving estimation. The second activity of the improvement project was to conduct interviews with project managers and senior developers about how to obtain continued and more widespread use of the method in the company. Based on the interviews, we propose a tailored, potentially improved version of the method and suggest how estimation practices can be improved by applying it. We believe that these experiences may be of interest to other companies that consider applying use case models as part of their estimation practices.},
	isbn = {3-540-00234-0},
	author = {Anda, Bente Cecilie Dahlum and Angelvik, E. and Ribu, K.},
	editor = {Anda, Bente Cecilie Dahlum}
}
@inproceedings {SE.5.Anda.2002.b,
	title = {Towards an Inspection Technique for Use Case Models},
	journal = {Fourteenth IEEE Conference on Software Engineering and Knowledge Engineering (SEKE{\textquoteright}02)},
	year = {2002},
	pages = {127-134},
	publisher = {-},
	type = {Conference},
	abstract = {A use case model describes the functional requirements of a software system and is used as input to several activities in a software development project. The quality of the use case model therefore has an important impact on the quality of the resulting software product. Software inspection is regarded as one of the most efficient methods for verifying software documents. There are inspection techniques for most documents produced in a software development project, but no comprehensive inspection technique exists for use case models. This paper gives an overview of typical defects in use case models and proposes a checklist-based inspection technique for detecting such defects. This inspection technique was evaluated in two studies with undergraduate students as subjects. The results indicate that inspections are useful for detecting defects in use case models. However, more work is needed to establish appropriate inspection techniques.},
	isbn = {1-58113-556-4},
	author = {Anda, Bente Cecilie Dahlum and Sj{\o}berg, Dag Ingar Kondrup},
	editor = {Anda, Bente Cecilie Dahlum}
}
@inproceedings {SE.5.Anda.2001.a,
	title = {Estimating Software Development Effort Based on Use Cases - Experiences From Industry},
	journal = {4th International Conference on the Unified Modeling Language (UML2001)},
	year = {2001},
	month = {October},
	pages = {487-502},
	publisher = {Springer-Verlag},
	type = {1},
	address = {Toronto, Canada},
	abstract = {Use case models are used in object-oriented analysis for capturing and describing the functional requirements of a system. Several methods for estimating software development effort are based on attributes of a use case model. This paper reports the results of three industrial case studies on the application of a method for effort estimation based on use case points. The aim of this paper is to provide guidance for other organizations that want to improve their estimation process applying use cases. Our results support existing claims that use cases can be used successfully in estimating software development effort. The results indicate that the guidance provided by the use case points method can support expert knowledge in the estimation process. Our experience is also that the design of the use case models has a strong impact on the estimates.},
	isbn = {3-540-42667-1},
	author = {Anda, Bente Cecilie Dahlum and Dreiem, Hege and Sj{\o}berg, Dag Ingar Kondrup and J{\o}rgensen, Magne},
	editor = {Gogolla, M. and Kobryn, C.}
}
@inproceedings {SE.5.Anda.2001.b,
	title = {Quality and Understandability of Use Case Models},
	journal = {ECOOP 2001 - Object-Oriented Programming, 15th European Conference},
	year = {2001},
	month = {June 18-22},
	pages = {402-428},
	publisher = {Springer-Verlag},
	type = {1},
	address = {Budapest, Hungary},
	abstract = {Use case models are used in object-oriented analysis for capturing and describing the functional requirements of a system. Use case models are also used in communication between stakeholders in development projects. It is therefore important that the use case models are constructed in such a way that they support the development process and promote a good understanding of the requirements among the stakeholders. Despite this, there are few guidelines on how to construct use case models. This paper describes an explorative study where three different sets of guidelines were used for constructing and documenting use case models. An experiment with 139 undergraduate students divided into 31 groups was conducted. Each group used one out of the three sets of guidelines when constructing a use case model from an informal requirements specification. After completing the use case model, each student answered a questionnaire. The results of the experiment indicate that guidelines based on templates support the construction of use case models that are easier to understand for the readers, than guidelines without specific details on how to document each use case. The guidelines based on templates were also considered as the most useful when constructing use cases. In addition to better understandability, our experiment indicates that the guidelines based on templates result in better use case models regarding also other quality attributes. Our results further indicate that it may be beneficial to combine the template guidelines with another set of guidelines that focus on the documentation of the flow of events of each use case. Keywords. Object-oriented analysis, Requirements specification, Use Cases, UML, Understandability, Experiment},
	isbn = {3-540-42206-4},
	author = {Anda, Bente Cecilie Dahlum and Sj{\o}berg, Dag Ingar Kondrup and J{\o}rgensen, Magne},
	editor = {Knudsen, Lindskov}
}
@inproceedings {SE.5.Joergensen.2000.b,
	title = {Human Judgement in Effort Estimation of Software Projects},
	journal = {Beg, Borrow, or Steal Workshop, International Conference on Software Engineering},
	year = {2000},
	month = {June},
	pages = {45-51},
	type = {Workshop},
	address = {Limerick, Ireland},
	author = {J{\o}rgensen, Magne and Kirkeb{\o}en, Geir and Sj{\o}berg, Dag Ingar Kondrup and Anda, Bente Cecilie Dahlum and Bratthall, Lars}
}
@inproceedings {SE.5.Anda.2000,
	title = {Understanding Use Case Models},
	journal = {Beg, Borrow, or Steal Workshop, International Conference on Software Engineering},
	year = {2000},
	month = {June 5,},
	pages = {94-102},
	publisher = {ICSE Workshop},
	type = {Workshop},
	address = {Limerick, Ireland},
	abstract = {Use Case Modeling is a technique for handling the functional requirements in a software development project. The Use Case Model can serve as a means of communication between the different stakeholders in a project. It is used in planning the project and is updated and used during the project. In order to reduce the possibilities for misunderstandings and differences in understanding, it would be useful to be able to evaluate to what extent the different stakeholders have understood the model and also to detect differences in interpretation. Low comprehension or differences in interpretation may indicate a need for more effort on specifying the requirements. If this is not feasible, it may be necessary to assume a higher risk when planning and estimating the project. We propose using knowledge on how humans understand text from cognitive psychology in the design of an experiment with a twofold goal: Investigate methods for measuring comprehension of Use Case Models and analyze the differences in understanding.},
	author = {Anda, Bente Cecilie Dahlum and J{\o}rgensen, Magne}
}
@inproceedings {SE.5.Arisholm.1999.c,
	title = {Guidelines on Conducting Software Process Improvement Studies in Industry},
	journal = {22nd IRIS Conference (Information Systems Research Seminar In Scandinavia)},
	year = {1999},
	month = {August 7-10,},
	pages = {87-102},
	type = {Conference},
	address = {Keuruu, Finland},
	author = {Arisholm, Erik and Anda, Bente Cecilie Dahlum and J{\o}rgensen, Magne and Sj{\o}berg, Dag Ingar Kondrup}
}
