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@article{DE_1972_8_5_a13, author = {V. I. Plotnikov and V. I. Sumin}, title = {Problems of the stability of nonlinear {Goursat--Darboux} systems}, journal = {Differencialʹnye uravneni\^a}, pages = {845--856}, publisher = {mathdoc}, volume = {8}, number = {5}, year = {1972}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1972_8_5_a13/} }
V. I. Plotnikov; V. I. Sumin. Problems of the stability of nonlinear Goursat--Darboux systems. Differencialʹnye uravneniâ, Tome 8 (1972) no. 5, pp. 845-856. http://geodesic.mathdoc.fr/item/DE_1972_8_5_a13/