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@article{DE_1992_28_7_a2, author = {A. P. Sadovskii}, title = {Focal values of a cubic system of nonlinear oscillations}, journal = {Differencialʹnye uravneni\^a}, pages = {1122--1127}, publisher = {mathdoc}, volume = {28}, number = {7}, year = {1992}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1992_28_7_a2/} }
A. P. Sadovskii. Focal values of a cubic system of nonlinear oscillations. Differencialʹnye uravneniâ, Tome 28 (1992) no. 7, pp. 1122-1127. http://geodesic.mathdoc.fr/item/DE_1992_28_7_a2/