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@article{IVM_1968_6_a9, author = {I. Z. Manevich}, title = {Existence of periodic solutions of a~system of three differential operators}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {75--76}, publisher = {mathdoc}, number = {6}, year = {1968}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1968_6_a9/} }
I. Z. Manevich. Existence of periodic solutions of a~system of three differential operators. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 6 (1968), pp. 75-76. http://geodesic.mathdoc.fr/item/IVM_1968_6_a9/