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@article{DE_1992_28_9_a25, author = {V. V. Stolyarov}, title = {A quadratic system with a limit cycle surrounded by a separatrix loop of a saddle}, journal = {Differencialʹnye uravneni\^a}, pages = {1643--1644}, publisher = {mathdoc}, volume = {28}, number = {9}, year = {1992}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1992_28_9_a25/} }
V. V. Stolyarov. A quadratic system with a limit cycle surrounded by a separatrix loop of a saddle. Differencialʹnye uravneniâ, Tome 28 (1992) no. 9, pp. 1643-1644. http://geodesic.mathdoc.fr/item/DE_1992_28_9_a25/