Consequences of the validity of Huygens' principle for the conformally invariant scalar wave equation, Weyl's neutrino equation and Maxwell's equations on Petrov type II space-times

Carminati, J.; Czapor, S. R.; McLenaghan, R. G.; Williams, G. C.

Annales de l'I.H.P. Physique théorique, Volume 54 (1991) p. 9-16