@article{EJDE_2002__2002__a44,
     author = {El Kahoui, M'hammed},
     title = {On plane polynomial vector fields and the {Poincar\'e} problem},
     journal = {Electronic Journal of Differential Equations},
     publisher = {mathdoc},
     volume = {2002},
     year = {2002},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2002__2002__a44/}
}