%0 Journal Article %A M. A. Valiev %T Asymptotic solution of differential equations in a Hilbert space %J Differencialʹnye uravneniâ %D 1977 %P 992-995 %V 13 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1977_13_6_a2/ %G ru %F DE_1977_13_6_a2