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@article{DE_1987_23_10_a14, author = {L. M. Nevostruev}, title = {Darboux problems for hyperbolic equations with degeneration of type and order}, journal = {Differencialʹnye uravneni\^a}, pages = {1780--1786}, publisher = {mathdoc}, volume = {23}, number = {10}, year = {1987}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1987_23_10_a14/} }
L. M. Nevostruev. Darboux problems for hyperbolic equations with degeneration of type and order. Differencialʹnye uravneniâ, Tome 23 (1987) no. 10, pp. 1780-1786. http://geodesic.mathdoc.fr/item/DE_1987_23_10_a14/