%0 Journal Article %A B. R. Vainberg %T Hypo-elliptic equations in the whole space and the principle of limiting absorption %J Doklady Akademii Nauk %D 1964 %P 20-23 %V 155 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1964_155_1_a3/ %G ru %F DAN_1964_155_1_a3