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@article{DE_1974_10_5_a23, author = {L. A. Cherkas and L. I. Zhilevich}, title = {\"Uber {Grenzzyklen} einer quadratischen {Differentialgleichung}}, journal = {Differencialʹnye uravneni\^a}, pages = {947--949}, publisher = {mathdoc}, volume = {10}, number = {5}, year = {1974}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1974_10_5_a23/} }
L. A. Cherkas; L. I. Zhilevich. \"Uber Grenzzyklen einer quadratischen Differentialgleichung. Differencialʹnye uravneniâ, Tome 10 (1974) no. 5, pp. 947-949. http://geodesic.mathdoc.fr/item/DE_1974_10_5_a23/