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@article{DE_1980_16_3_a5, author = {G. S. Rychkov}, title = {Uniqueness of the limit cycle of the equation $(y-P_3(x))dy=P_1(x,y)dx$}, journal = {Differencialʹnye uravneni\^a}, pages = {433--437}, publisher = {mathdoc}, volume = {16}, number = {3}, year = {1980}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1980_16_3_a5/} }
G. S. Rychkov. Uniqueness of the limit cycle of the equation $(y-P_3(x))dy=P_1(x,y)dx$. Differencialʹnye uravneniâ, Tome 16 (1980) no. 3, pp. 433-437. http://geodesic.mathdoc.fr/item/DE_1980_16_3_a5/