1. B. R. Wienke:Phys. Rev. D,7, 2253 (1973).
2. V. S. Mathur andS. Okubo:Phys. Rev.,181, 2148 (1969).
3. S. Okubo:Proceedings of the 1967 International Conference on Particles and Fields (New York, 1967), p. 469 and references given therein:T. Das, V. S. Mathur andS. Okubo:Phys. Rev. Lett.,19, 1067 (1967).
4. S. Okubo:Proceedings of the 1967 International Conference on Particles and Fields (New York, 1967) p. 469 and references given therein;A. N. Kamal:Nucl. Phys.,12 B, 123 (1969);
5. H. T. Nich:Phys. Rev.,163, 1769 (1967);