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@article{DE_1987_23_5_a14, author = {L. A. Cherkas}, title = {Limit cycles of autonomous systems with phase space $\mathbf C^2$}, journal = {Differencialʹnye uravneni\^a}, pages = {848--851}, publisher = {mathdoc}, volume = {23}, number = {5}, year = {1987}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1987_23_5_a14/} }
L. A. Cherkas. Limit cycles of autonomous systems with phase space $\mathbf C^2$. Differencialʹnye uravneniâ, Tome 23 (1987) no. 5, pp. 848-851. http://geodesic.mathdoc.fr/item/DE_1987_23_5_a14/