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@article{IVM_1962_6_a16, author = {A. Ya. Khokhryakov}, title = {On the generation of limit cycles}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {145--147}, publisher = {mathdoc}, number = {6}, year = {1962}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1962_6_a16/} }
A. Ya. Khokhryakov. On the generation of limit cycles. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 6 (1962), pp. 145-147. http://geodesic.mathdoc.fr/item/IVM_1962_6_a16/