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@article{DE_1971_7_8_a19, author = {L. I. Zhilevich}, title = {On the question of separatrices and limit cycles of a certain differential equation}, journal = {Differencialʹnye uravneni\^a}, pages = {1525--1527}, publisher = {mathdoc}, volume = {7}, number = {8}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1971_7_8_a19/} }
L. I. Zhilevich. On the question of separatrices and limit cycles of a certain differential equation. Differencialʹnye uravneniâ, Tome 7 (1971) no. 8, pp. 1525-1527. http://geodesic.mathdoc.fr/item/DE_1971_7_8_a19/