Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1975_11_8_a18, author = {I. A. Konoplyannik}, title = {A certain class of third order systems without movable critical points}, journal = {Differencialʹnye uravneni\^a}, pages = {1508--1511}, publisher = {mathdoc}, volume = {11}, number = {8}, year = {1975}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1975_11_8_a18/} }
I. A. Konoplyannik. A certain class of third order systems without movable critical points. Differencialʹnye uravneniâ, Tome 11 (1975) no. 8, pp. 1508-1511. http://geodesic.mathdoc.fr/item/DE_1975_11_8_a18/