@article{EJDE_2000__2000__a62,
     author = {Boularas,  D.},
     title = {A note on the saddle conic of quadratic planar differential systems},
     journal = {Electronic journal of differential equations},
     year = {2000},
     volume = {2000},
     zbl = {0947.34012},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2000__2000__a62/}
}