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@article{IVM_1960_3_a4, author = {E. A. Barbashin and \`E. V. Vdovina}, title = {Uniqueness conditions for limit cycles}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {43--47}, publisher = {mathdoc}, number = {3}, year = {1960}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1960_3_a4/} }
E. A. Barbashin; È. V. Vdovina. Uniqueness conditions for limit cycles. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 3 (1960), pp. 43-47. http://geodesic.mathdoc.fr/item/IVM_1960_3_a4/