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@article{IVM_1958_3_a4, author = {I. M. Volk}, title = {On periodic solutions of quasi-linear differential equations in certain cases}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {31--40}, publisher = {mathdoc}, number = {3}, year = {1958}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1958_3_a4/} }
I. M. Volk. On periodic solutions of quasi-linear differential equations in certain cases. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 3 (1958), pp. 31-40. http://geodesic.mathdoc.fr/item/IVM_1958_3_a4/