@article{1200689165,
author = {Nagumo, Mitio and Is\'e, Kusuo},
title = {On the normal forms of differential equations in the neighborhood of an equilibrium point},
journal = {Osaka Math. J.},
volume = {9},
number = {1},
year = {1957},
pages = { 221-234},
language = {en},
url = {http://dml.mathdoc.fr/item/1200689165}
}
Nagumo, Mitio; Isé, Kusuo. On the normal forms of differential equations in the neighborhood of an equilibrium point. Osaka Math. J., Tome 9 (1957) no. 1, pp. 221-234. http://gdmltest.u-ga.fr/item/1200689165/