@article{SM_1977_33_2_a6,
     author = {V. P. Tanana},
     title = {On optimal algorithms for operator equations of the first kind with a~perturbed operator},
     journal = {Sbornik. Mathematics},
     pages = {281--297},
     publisher = {mathdoc},
     volume = {33},
     number = {2},
     year = {1977},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1977_33_2_a6/}
}