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@article{DE_1987_23_4_a5, author = {L. I. Zhilevich}, title = {On periodic solutions of the {Li\'enard} equation}, journal = {Differencialʹnye uravneni\^a}, pages = {608--611}, publisher = {mathdoc}, volume = {23}, number = {4}, year = {1987}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1987_23_4_a5/} }
L. I. Zhilevich. On periodic solutions of the Li\'enard equation. Differencialʹnye uravneniâ, Tome 23 (1987) no. 4, pp. 608-611. http://geodesic.mathdoc.fr/item/DE_1987_23_4_a5/