• [1]

    H. D. Politzer, Phys. Rev. Lett., 30(1973), 1346. D. H. Gross and F. Wilczek, Phys. Rev.Lett.,30(1973), 1343.[2] E. Ma and J. Okada, Phys. .Rev. Lett., 41(1978), 287.[3] G. Steigman et aL, Phys. Lett., 66B(1977), 202.[4] S. Weinberg, X IX International Conference on High Energy Physics, Tokyo (1978).[5] H. Harari,Physics Reports., 42C(1978), 238.[6] D. Bjorken, SLAC-pub., 2195(1978).