%0 Journal Article
%A N. N. Gaidai
%T Existence of the spectrum for the Tricomi operator
%J Differencialʹnye uravneniâ
%D 1981
%P 31-38
%V 17
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1981_17_1_a4/
%G ru
%F DE_1981_17_1_a4