%0 Journal Article %A M. D. Ramazanov %T A priori estimates of solutions of the Dirichlet problem for certain hypoelliptic equations %J Doklady Akademii Nauk %D 1968 %P 783-785 %V 179 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1968_179_4_a7/ %G ru %F DAN_1968_179_4_a7