Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1967_3_3_a0, author = {V. V. Nemytskii}, title = {Topological classification of singular points and generalized {Ljapunov} functions}, journal = {Differencialʹnye uravneni\^a}, pages = {359--370}, publisher = {mathdoc}, volume = {3}, number = {3}, year = {1967}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1967_3_3_a0/} }
V. V. Nemytskii. Topological classification of singular points and generalized Ljapunov functions. Differencialʹnye uravneniâ, Tome 3 (1967) no. 3, pp. 359-370. http://geodesic.mathdoc.fr/item/DE_1967_3_3_a0/