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@article{DE_1978_14_1_a8, author = {N. I. Popivanov}, title = {A multidimensional analogue of the {Darboux} problem for degenerate hyperbolic equations}, journal = {Differencialʹnye uravneni\^a}, pages = {80--93}, publisher = {mathdoc}, volume = {14}, number = {1}, year = {1978}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1978_14_1_a8/} }
N. I. Popivanov. A multidimensional analogue of the Darboux problem for degenerate hyperbolic equations. Differencialʹnye uravneniâ, Tome 14 (1978) no. 1, pp. 80-93. http://geodesic.mathdoc.fr/item/DE_1978_14_1_a8/