%0 Journal Article
%A O. A. Oleinik
%A E. V. Radkevich
%T On local smoothness of generalized and hypoellipticity of second order differential equations
%J Trudy Matematicheskogo Instituta imeni V.A. Steklova
%D 1971
%P 139-156
%V 26
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/RM_1971_26_2_a8/
%G en
%F RM_1971_26_2_a8