%0 Journal Article
%A Yu. V. Egorov
%T Necessary conditions for the solvability of pseudodifferential equations of principal type
%J Trudy Moskovskogo matematičeskogo obŝestva
%D 1971
%P 29-41
%V 24
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MMO_1971_24_a1/
%G ru
%F MMO_1971_24_a1