%0 Journal Article
%A B. N. Khimchenko
%T On a theorem of M. V. Keldysh and M. A. Lavrent’ev
%J Doklady Akademii Nauk
%D 1970
%P 46-47
%V 192
%N 1
%U http://geodesic.mathdoc.fr/item/DAN_1970_192_1_a10/
%G ru
%F DAN_1970_192_1_a10