The Cauchy problem for coupled Yang-Mills and scalar fields in the Lorentz gauge J. Ginibre, G. Velo (1982) Annales de l'I.H.P. Physique théorique
The existence of global solutions to the elliptic-hyperbolic Davey-Stewartson system with small initial data Hayashi, Nakao, Hirata, Hitoshi (1998) Proceedings of Equadiff 9