H. P. Dürr, W. Heisenberg, H. Mitter, S. Schlieder andK. Yamazaki:Zeits. f. Naturf.,14 a, 441 (1959).
J. Dhar andY. Katayama:Conf. on High Energy Physics in Dubna (1964);Nuovo Cimento,36, 533 (1965).
H. P. Dürr:Zeits. f. Naturf.,16 a, 327 (1961).
H. P. Dürr, W. Heisenberg, H. Yamamoto andK. Yamazaki:Quantum electrodynamics in the nonlinear spinor theory and the value of Sommerfeld’s fine structure constant (to be published inNuovo Cimento).
W. Heisenberg:Nucl. Phys.,4, 532 (1957);R. Hüper:Zeits. f. Naturf.,17a, 380 (1962).