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@article{DE_1989_25_6_a19, author = {E. E. Barbashina}, title = {Necessary conditions of {Copa--Moir} type for a {Goursat--Darboux} system}, journal = {Differencialʹnye uravneni\^a}, pages = {1045--1047}, publisher = {mathdoc}, volume = {25}, number = {6}, year = {1989}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1989_25_6_a19/} }
E. E. Barbashina. Necessary conditions of Copa--Moir type for a Goursat--Darboux system. Differencialʹnye uravneniâ, Tome 25 (1989) no. 6, pp. 1045-1047. http://geodesic.mathdoc.fr/item/DE_1989_25_6_a19/