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@article{IVM_1968_4_a5, author = {S. Karimov}, title = {Periodic solutions of nonlinear systems of difference equations in two variables}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {33--39}, publisher = {mathdoc}, number = {4}, year = {1968}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1968_4_a5/} }
S. Karimov. Periodic solutions of nonlinear systems of difference equations in two variables. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 4 (1968), pp. 33-39. http://geodesic.mathdoc.fr/item/IVM_1968_4_a5/