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@article{DE_1970_6_8_a21, author = {O. A. Kononova}, title = {The limit cycles of a certain system of nonlinear oscillations}, journal = {Differencialʹnye uravneni\^a}, pages = {1514--1515}, publisher = {mathdoc}, volume = {6}, number = {8}, year = {1970}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1970_6_8_a21/} }
O. A. Kononova. The limit cycles of a certain system of nonlinear oscillations. Differencialʹnye uravneniâ, Tome 6 (1970) no. 8, pp. 1514-1515. http://geodesic.mathdoc.fr/item/DE_1970_6_8_a21/