@article {SC.4.Cai.1999,
	title = {An Analysis of a Preconditioner for the Discretized Pressure Equation Arising in Reservoir Simulation},
	journal = {IMA Journal of Numerical Analysis},
	volume = {19},
	number = {2},
	year = {1999},
	pages = {291-316},
	author = {Cai, Xing and Nielsen, Bj{\o}rn Fredrik and Tveito, Aslak}
}
