Saddle-focus singular cycles and prevalence of hyperbolicity Bernardo San Martín — 1998 Annales de l'I.H.P. Analyse non linéaire
Nonhyperbolic persistent attractors near the Morse–Smale boundary Eduardo M Muñoz Morales; Bernardo San Martín Rebolledo; Jaime A Vera Valenzuela — 2003 Annales de l'I.H.P. Analyse non linéaire