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@article{DE_1994_30_9_a1, author = {V. N. Gorbuzov}, title = {On a second-order differential system and its periodic solutions}, journal = {Differencialʹnye uravneni\^a}, pages = {1487--1497}, publisher = {mathdoc}, volume = {30}, number = {9}, year = {1994}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1994_30_9_a1/} }
V. N. Gorbuzov. On a second-order differential system and its periodic solutions. Differencialʹnye uravneniâ, Tome 30 (1994) no. 9, pp. 1487-1497. http://geodesic.mathdoc.fr/item/DE_1994_30_9_a1/