$e^+e^-$ pair production in relativistic ions collision and its   correspondence to electron-ion scattering
  It is shown that the amplitudes of electron-ion scattering and $e^+e^-$ pair production in the Coulomb field of two colliding ions are sxpressed in the terms of electron scattering amplitudes in the fields of the individual ions via the Watson expansion. We have obtained the compact expressions for these amplitudes valid in the high energy limit and discuss the crossing symmetry relations among the considered processes. 
A.N. Sissakian, A.V. Tarasov, H.T. Torosyan and O.O. Voskresenskaya