Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_2003_39_4_a4, author = {A. P. Sadovskii}, title = {Cubic {Systems} of {Nonlinear} {Oscillations} with {Seven} {Limit} {Cycles}}, journal = {Differencialʹnye uravneni\^a}, pages = {472--481}, publisher = {mathdoc}, volume = {39}, number = {4}, year = {2003}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_2003_39_4_a4/} }
A. P. Sadovskii. Cubic Systems of Nonlinear Oscillations with Seven Limit Cycles. Differencialʹnye uravneniâ, Tome 39 (2003) no. 4, pp. 472-481. http://geodesic.mathdoc.fr/item/DE_2003_39_4_a4/