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@article{IVM_1968_8_a12, author = {S. M. Shaova}, title = {The cycles of a~certain differential equation}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {96--102}, publisher = {mathdoc}, number = {8}, year = {1968}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1968_8_a12/} }
S. M. Shaova. The cycles of a~certain differential equation. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 8 (1968), pp. 96-102. http://geodesic.mathdoc.fr/item/IVM_1968_8_a12/