%0 Journal Article
%A L. R. Volevich
%T On hypo-elliptic systems with variable coefficients
%J Doklady Akademii Nauk
%D 1964
%P 1262-1265
%V 156
%N 6
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1964_156_6_a2/
%G ru
%F DAN_1964_156_6_a2