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2. J. M. Charap: see for instance:Complex angular momentum theory of particles with spin, inElementary Particles and High Energy Physics, edited byM. Lévy andPh. Meyer (1963), where references to the original literature can be found.
3. L. Wang:Phys. Rev.,142, 1187 (1966).
4. L. Wang:Phys. Rev.,153, 1664 (1967).
5. D. V. Volkov andV. N. Gribov:Žurn. Ėksp. Teor. Fiz.,17, 720 (1963).