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@article{DE_1999_35_8_a17, author = {A. P. Begun}, title = {On the number of periodic solutions generated by a singular periodic solution}, journal = {Differencialʹnye uravneni\^a}, pages = {1132--1134}, publisher = {mathdoc}, volume = {35}, number = {8}, year = {1999}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1999_35_8_a17/} }
A. P. Begun. On the number of periodic solutions generated by a singular periodic solution. Differencialʹnye uravneniâ, Tome 35 (1999) no. 8, pp. 1132-1134. http://geodesic.mathdoc.fr/item/DE_1999_35_8_a17/