On the point limit of the Pauli-Fierz model Diego Noja; Andrea Posilicano — 1999 Annales de l'I.H.P. Physique théorique
The wave equation with one point interaction and the (linearized) classical electrodynamics of a point particle Diego Noja; Andrea Posilicano — 1998 Annales de l'I.H.P. Physique théorique