%0 Journal Article %A G. L. Chernyshev %T On the Friedrichs--Lewy inequality for $B$-hyperbolic operators %J Doklady Akademii Nauk %D 1971 %P 1295-1298 %V 201 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1971_201_6_a7/ %G ru %F DAN_1971_201_6_a7