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@article{DE_1999_35_1_a0, author = {V. V. Amel'kin and A. B. Levin}, title = {A criterion for the stability of multiple limit cycles}, journal = {Differencialʹnye uravneni\^a}, pages = {3--7}, publisher = {mathdoc}, volume = {35}, number = {1}, year = {1999}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1999_35_1_a0/} }
V. V. Amel'kin; A. B. Levin. A criterion for the stability of multiple limit cycles. Differencialʹnye uravneniâ, Tome 35 (1999) no. 1, pp. 3-7. http://geodesic.mathdoc.fr/item/DE_1999_35_1_a0/