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@article{DE_1983_19_4_a1, author = {N. I. Vulpe}, title = {Minimal complete system of orthogonal invariants of a two-dimensional differential system}, journal = {Differencialʹnye uravneni\^a}, pages = {564--569}, publisher = {mathdoc}, volume = {19}, number = {4}, year = {1983}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1983_19_4_a1/} }
N. I. Vulpe. Minimal complete system of orthogonal invariants of a two-dimensional differential system. Differencialʹnye uravneniâ, Tome 19 (1983) no. 4, pp. 564-569. http://geodesic.mathdoc.fr/item/DE_1983_19_4_a1/