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@article{DAN_1971_201_6_a7, author = {G. L. Chernyshev}, title = {On the {Friedrichs--Lewy} inequality for $B$-hyperbolic operators}, journal = {Doklady Akademii Nauk}, pages = {1295--1298}, publisher = {mathdoc}, volume = {201}, number = {6}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1971_201_6_a7/} }
G. L. Chernyshev. On the Friedrichs--Lewy inequality for $B$-hyperbolic operators. Doklady Akademii Nauk, Tome 201 (1971) no. 6, pp. 1295-1298. http://geodesic.mathdoc.fr/item/DAN_1971_201_6_a7/