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@article{DE_1988_24_12_a16, author = {N. Radjabov}, title = {A second-order equation of hyperbolic type with two singular lines}, journal = {Differencialʹnye uravneni\^a}, pages = {2129--2133}, publisher = {mathdoc}, volume = {24}, number = {12}, year = {1988}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1988_24_12_a16/} }
N. Radjabov. A second-order equation of hyperbolic type with two singular lines. Differencialʹnye uravneniâ, Tome 24 (1988) no. 12, pp. 2129-2133. http://geodesic.mathdoc.fr/item/DE_1988_24_12_a16/