@article{GDZPPN001184288, title = {On block diagonal and Schur complement preconditioning.}, journal = {Numerische Mathematik}, volume = {58}, year = {1990}, pages = {79-94}, zbl = {0687.65036}, url = {http://dml.mathdoc.fr/item/GDZPPN001184288} }
Mandel, Jan. On block diagonal and Schur complement preconditioning.. Numerische Mathematik, Tome 58 (1990) pp. 79-94. http://gdmltest.u-ga.fr/item/GDZPPN001184288/