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@article{DE_1971_7_2_a17, author = {Z. M. Kochetkova}, title = {The isochrony of a certain system of differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {359--362}, publisher = {mathdoc}, volume = {7}, number = {2}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1971_7_2_a17/} }
Z. M. Kochetkova. The isochrony of a certain system of differential equations. Differencialʹnye uravneniâ, Tome 7 (1971) no. 2, pp. 359-362. http://geodesic.mathdoc.fr/item/DE_1971_7_2_a17/