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@article{MI_1971__6_4_189112, author = {{\CYRI}.{\CYRI}. {\CYRP}{\cyrl}{\cyre}{\cyrsh}{\cyrk}{\cyra}{\cyrn} and {\CYRK}.{\CYRS}. {\CYRS}{\cyri}{\cyrb}{\cyri}{\cyrr}{\cyrs}{\cyrk}{\cyri}{\cyrishrt}}, title = {{\CYRI}{\cyrz}{\cyro}{\cyrh}{\cyrr}{\cyro}{\cyrn}{\cyrn}{\cyro}{\cyrs}{\cyrt}{\cyrsftsn} {\cyrs}{\cyri}{\cyrs}{\cyrt}{\cyre}{\cyrm}{\cyrery} {\cyrs} {\cyrk}{\cyrv}{\cyra}{\cyrd}{\cyrr}{\cyra}{\cyrt}{\cyri}{\cyrch}{\cyrn}{\cyrery}{\cyrm}{\cyri} {\cyrn}{\cyre}{\cyrl}{\cyri}{\cyrn}{\cyre}{\cyrishrt}{\cyrn}{\cyro}{\cyrs}{\cyrt}{\cyrya}{\cyrm}{\cyri}}, journal = {Matemati\v{c}eskie issledovani\^a}, pages = {140--154}, publisher = {mathdoc}, volume = {6}, number = {4}, year = {1971}, zbl = {0244.34017}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MI_1971__6_4_189112/} }
И.И. Плешкан; К.С. Сибирский. Изохронность системы с квадратичными нелинейностями. Matematičeskie issledovaniâ, Tome 6 (1971) no. 4, pp. 140-154. http://geodesic.mathdoc.fr/item/MI_1971__6_4_189112/