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@article{IVM_1982_7_a7, author = {A. I. Perov and V. L. Khatskevich}, title = {Some local existence theorems for periodic solutions}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {50--60}, publisher = {mathdoc}, number = {7}, year = {1982}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1982_7_a7/} }
A. I. Perov; V. L. Khatskevich. Some local existence theorems for periodic solutions. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 7 (1982), pp. 50-60. http://geodesic.mathdoc.fr/item/IVM_1982_7_a7/