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@article{DE_1990_26_2_a19, author = {E. E. Barbashina}, title = {Necessary conditions with matrix impulses for a {Goursat--Darboux} system}, journal = {Differencialʹnye uravneni\^a}, pages = {342--343}, publisher = {mathdoc}, volume = {26}, number = {2}, year = {1990}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1990_26_2_a19/} }
E. E. Barbashina. Necessary conditions with matrix impulses for a Goursat--Darboux system. Differencialʹnye uravneniâ, Tome 26 (1990) no. 2, pp. 342-343. http://geodesic.mathdoc.fr/item/DE_1990_26_2_a19/