@techreport {Petra-et-al08b,
	title = {Extended and Constrained Cimmino-type Algorithms with Applications in Tomographic Image Reconstruction},
	year = {2008},
	institution = {IWR, University of Heidelberg},
	url = {http://www.ub.uni-heidelberg.de/archiv/8798/},
	author = {Stefania Petra and Popa, Constantin and Christoph Schn{\"o}rr}
}
