@article{DE_1992_28_2_a16,
     author = {I. E. Kaporin},
     title = {Two-level explicit preconditionings for the conjugate gradient method},
     journal = {Differencialʹnye uravneni\^a},
     pages = {329--339},
     publisher = {mathdoc},
     volume = {28},
     number = {2},
     year = {1992},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1992_28_2_a16/}
}