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@article{DE_1977_13_8_a10, author = {V. Kh. Froim}, title = {Some partial differential equations that are degenerate on a hyperplane}, journal = {Differencialʹnye uravneni\^a}, pages = {1446--1453}, publisher = {mathdoc}, volume = {13}, number = {8}, year = {1977}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1977_13_8_a10/} }
V. Kh. Froim. Some partial differential equations that are degenerate on a hyperplane. Differencialʹnye uravneniâ, Tome 13 (1977) no. 8, pp. 1446-1453. http://geodesic.mathdoc.fr/item/DE_1977_13_8_a10/