• [1]

    E.Witten,Nucl.Phys,B185(1981)513.[2] P.Solomonson,J.W.VanHolten,Nucl.Phys.,B196(1982)262;F.Cooper,B.Freedman.Ann.Phys.(N.Y.),146(1988)262;C.V.Sukumar,J.Phys.,A18(1985)2917;2937.R.Roy,R.Roychoudhury,Phys.Lett,A122(1987)275;H.Ui,Prog.Theor.Phys.,72(1984)813,192.[3] M.De Crombrugghe,V.Rittenberg,Ann.Phys.(N.Y.),51(1983)99.[4] A.I.Pashnev,Teor.Mat.Fiz.(Sov),69(1986)311;V.P.Berezovj.A.I.Paxhnev,Z.Phys.,C51(1991)525.