%0 Journal Article %A V. V. Fedorchuk %T On a problem of A. N. Tihonov %J Doklady Akademii Nauk %D 1973 %P 1297-1299 %V 210 %N 6 %U http://geodesic.mathdoc.fr/item/DAN_1973_210_6_a11/ %G ru %F DAN_1973_210_6_a11