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@article{DE_1969_5_7_a21, author = {N. I. Avdonin}, title = {Examples of the generation of a limit cycle from a separatrix loop and a singular cycle}, journal = {Differencialʹnye uravneni\^a}, pages = {1335--1337}, publisher = {mathdoc}, volume = {5}, number = {7}, year = {1969}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1969_5_7_a21/} }
N. I. Avdonin. Examples of the generation of a limit cycle from a separatrix loop and a singular cycle. Differencialʹnye uravneniâ, Tome 5 (1969) no. 7, pp. 1335-1337. http://geodesic.mathdoc.fr/item/DE_1969_5_7_a21/