%0 Journal Article %A S. V. Uspenskii %T The summability (boundedness) of the solutions of a certain class of hypoelliptic equations in unbounded domains %J Doklady Akademii Nauk %D 1969 %P 998-1001 %V 187 %N 5 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1969_187_5_a9/ %G ru %F DAN_1969_187_5_a9