%0 Journal Article
%A G. I. Laptev
%T Eigenvalue problems for differential equations of the second order in Banach and Hilbert spaces
%J Differencialʹnye uravneniâ
%D 1966
%P 1151-1160
%V 2
%N 9
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1966_2_9_a1/
%G ru
%F DE_1966_2_9_a1