%0 Journal Article
%A P. R. Popivanov
%T Hypoellipticity of differential operators in the class of generalized periodic functions
%J Doklady Akademii Nauk
%D 1982
%P 565-568
%V 266
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1982_266_3_a11/
%G ru
%F DAN_1982_266_3_a11