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@article{DE_1978_14_2_a1, author = {N. N. Vasil'eva}, title = {Separatrices of saddle periodic solutions of {Duffing's} equation}, journal = {Differencialʹnye uravneni\^a}, pages = {201--211}, publisher = {mathdoc}, volume = {14}, number = {2}, year = {1978}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1978_14_2_a1/} }
N. N. Vasil'eva. Separatrices of saddle periodic solutions of Duffing's equation. Differencialʹnye uravneniâ, Tome 14 (1978) no. 2, pp. 201-211. http://geodesic.mathdoc.fr/item/DE_1978_14_2_a1/