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@article{DAN_1986_287_3_a4, author = {E. M. Vorob'ev}, title = {Partial symmetries of systems of differential equations}, journal = {Doklady Akademii Nauk}, pages = {536--539}, publisher = {mathdoc}, volume = {287}, number = {3}, year = {1986}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1986_287_3_a4/} }
E. M. Vorob'ev. Partial symmetries of systems of differential equations. Doklady Akademii Nauk, Tome 287 (1986) no. 3, pp. 536-539. http://geodesic.mathdoc.fr/item/DAN_1986_287_3_a4/