@article{05627897, title = {The return map for a planar vector field with nilpotent linear part: a direct and explicit derivation.}, journal = {International Journal of Mathematics and Mathematical Sciences}, volume = {2009}, year = {2009}, doi = {10.1155/2009/590856}, zbl = {1179.37026}, language = {en}, url = {http://dml.mathdoc.fr/item/05627897} }
Costin, Rodica D. The return map for a planar vector field with nilpotent linear part: a direct and explicit derivation.. International Journal of Mathematics and Mathematical Sciences, Tome 2009 (2009) . doi : 10.1155/2009/590856. http://gdmltest.u-ga.fr/item/05627897/