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@article{DE_1993_29_2_a6, author = {D. S. Ushkho}, title = {On the number of singular points of the second group of a cubic system}, journal = {Differencialʹnye uravneni\^a}, pages = {240--245}, publisher = {mathdoc}, volume = {29}, number = {2}, year = {1993}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1993_29_2_a6/} }
D. S. Ushkho. On the number of singular points of the second group of a cubic system. Differencialʹnye uravneniâ, Tome 29 (1993) no. 2, pp. 240-245. http://geodesic.mathdoc.fr/item/DE_1993_29_2_a6/