%0 Journal Article %A A. T. Taldykin %T Systems of elements of a space over a space, and variational methods for the solution of equations with variable operators %J Differencialʹnye uravneniâ %D 1977 %P 724-732 %V 13 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1977_13_4_a15/ %G ru %F DE_1977_13_4_a15