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@article{DE_1972_8_1_a6, author = {G. D. Karatoprakliev}, title = {Equations of mixed type and degenerate hyperbolic equations in multidimensional domains}, journal = {Differencialʹnye uravneni\^a}, pages = {55--67}, publisher = {mathdoc}, volume = {8}, number = {1}, year = {1972}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1972_8_1_a6/} }
G. D. Karatoprakliev. Equations of mixed type and degenerate hyperbolic equations in multidimensional domains. Differencialʹnye uravneniâ, Tome 8 (1972) no. 1, pp. 55-67. http://geodesic.mathdoc.fr/item/DE_1972_8_1_a6/