1. J.-P. Vigier,C. R. Acad. Sci. Paris B 279, 1 (1974).
2. D. Bohm and J.-P. Vigier,Phys. Rev. 109, 1882 (1958).
3. Hara and Gota, Preprint, Dept. of Theor. Phys. NUP, A-68-8, Nihon Univ., Tokyo.
4. W. Glaser,Z. Phys. 139, 276 (1954).
5. G. B. Cvijanovich, Habil. Thesis, Univ. of Bern, 1964; and Preprint, Dept. of Physics, Upsala College, East Orange, 1970; submitted toInt. J. Theor. Phys.