%0 Journal Article
%A A. M. Nakhushev
%T A three-dimensional analog of Gellerstedt's problem
%J Differencialʹnye uravneniâ
%D 1968
%P 52-62
%V 4
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1968_4_1_a4/
%G ru
%F DE_1968_4_1_a4