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@article{DE_2003_39_6_a4, author = {L. A. Cherkas}, title = {A {Precise} {Estimate} of the {Number} of {Limit} {Cycles} of {Autonomous} {Systems} on the {Plane}}, journal = {Differencialʹnye uravneni\^a}, pages = {759--768}, publisher = {mathdoc}, volume = {39}, number = {6}, year = {2003}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_2003_39_6_a4/} }
L. A. Cherkas. A Precise Estimate of the Number of Limit Cycles of Autonomous Systems on the Plane. Differencialʹnye uravneniâ, Tome 39 (2003) no. 6, pp. 759-768. http://geodesic.mathdoc.fr/item/DE_2003_39_6_a4/