1. M. Carmeli andM. Kaye:Nuovo Cimento,34 B, 225 (1976);Lett. Nuovo Cimento,17, 275 (1976).
2. M. Carmeli:SL 2C ,symmetry of the gravitational field, inGroup Theory in Nonlinear Problems (1972 NATO Advanced Study Institute on Mathematical Physics, Istanbul, Turkey), edited byA. O. Barut (Dordrecht, 1974), p. 59.
3. M. Carmeli:Group Theory and General Relativity (New York, 1977).
4. M. Carmeli:Phys. Rev. Lett.,36, 59 (1976).
5. M. Carmeli andS. I. Fickler:Phys. Rev. D,5, 290 (1972).