Geodesics on product lorentzian manifolds F. Giannoni; A. Masiello — 1995 Annales de l'I.H.P. Analyse non linéaire
On the geodesic connectedeness of Lorentzian manifolds. V. Benci; D. Fortunato; A. Masiello — 1994 Mathematische Zeitschrift
A Morse theory for light rays on stably causal lorentzian manifolds F. Giannoni; A. Masiello; P. Piccione — 1998 Annales de l'I.H.P. Physique théorique