Artés Joan C.; Mota Marcos C.; Rezende Alex C.: Structurally unstable quadratic vector fields of codimension two : families possessing a finite saddle-node and an infinite saddle-node. (2021)
Artés Joan C.; Llibre Jaume; Rezende Alex C.; Schlomiuk Dana; Vulpe Nicolae: Global configurations of singularities for quadratic differential systems with exactly two finite singularities of total multiplicity four. (2014)