Abel equations are among the most natural ordinary differential equations which have a Godbillon-Vey sequence of length 4. We show that the associated Poincaré mapping can be expressed by iterated integrals with three functions which are solutions of a system of partial differential equations.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-bc94-0-11,
author = {Jean-Pierre Fran\c coise},
title = {Integrability and limit cycles for Abel equations},
journal = {Banach Center Publications},
volume = {95},
year = {2011},
pages = {187-196},
zbl = {1248.34031},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-bc94-0-11}
}
Jean-Pierre Françoise. Integrability and limit cycles for Abel equations. Banach Center Publications, Tome 95 (2011) pp. 187-196. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-bc94-0-11/