Invitations longue durée`
Université de Bloomington, Indiana, 1990, 1991.
Université Penn state, pensylvania, 1992, 1993.
Ecole normale supérieure de Lyon, 1992.
Université de Rome La sapienza,
un mois 2011, 2012, 2013.
Congrès récents :
Congrès
Luminy conference on Quasilinear Elliptic and
parabolic
equations and systems, 2001.
Cortone 2003 Seminario interdisciplinare di
matematica, workshop "Second Order subellliptic Equations
and applications.
Rome septembre 2008,
Viscosity methods, colloquium in the honor of Italo Capuzzo Dolcetta.
Vietri juin 2010, Positivity, a key for fully nonlinear partial
differntial equations.
Rome , september 2012, Mostly maximum principle