@inbook {Simula.sc.862,
	title = {Construction of Preconditioners by Mapping Properties for Systems of Partial Differential Equations},
	booktitle = {Efficient preconditioning methods for elliptic partial differential equations},
	year = {2011},
	pages = {65-84},
	publisher = {Bentham Science Publishers},
	organization = {Bentham Science Publishers},
	chapter = {4},
	isbn = {978-1-60805-291-2},
	author = {Mardal, Kent-Andre and Winther, Ragnar},
	editor = {Axelsson, Owe and Karatson, Janos}
}
