1. J. de Swart:Rev. Mod. Phys.,35, 916 (1963).
2. A. H. Rosenfeld, A. Barbaro-Galtieri, W. H. Barkas, P. L. Bastien, J. Kirz andM. Roos:Rev. Mod. Phys.,37, 633 (1965).
3. For example:M. Konuma, K. Shima andM. Wada:Suppl. Progr. Theor. Phys. (Kyoto),28, 1 (1963).
4. E. B. Dynkin:Trudy Mosk. Mat. Obshch,1, 39 (1952)Supplement. Translated inAm. Math. Soc. Transl., Ser. 2, vol.6 (1957), p. 245.
5. E. B. Dynkin:Mat. Sbornik N. S.,30, (72), 349 (1952). Translated inAm. Math. Soc. Transl., Ser. 2, vol.6 (1957), p. 111.