%0 Journal Article
%A A. Yu. Levin
%T On linear second-order differential equations
%J Doklady Akademii Nauk
%D 1963
%P 1257-1260
%V 153
%N 6
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1963_153_6_a7/
%G ru
%F DAN_1963_153_6_a7