1. M. Alonso and E.J. Finn: Fundamental University Physics, Vol.Ill (Addison-Wesley, Reading, Mass. 1968 ).
2. M. Alonso and E.J. Finn J. Anandan, Nuovo Cimento 53A, 221 (1979); J. Anandan and B. Lesche, Lett. Nuovo Cimento 37, 391 (1983).
3. D.K. Atwood, M.A. Hörne, C.G. Shull, and J. Arthur, Phys. Rev. Lett. 52, 1673 (1984).
4. J. Audretsch and C. Lämmerzahl, J. Phys. A16, 2457 (1983).
5. J. Audretsch and C. Lämmerzahl, Ann. Phys. (Leipzig) 44, 145 (1987).