The amplitude of lepton-pair production in relativistic ion collisions   beyond the perturbative theory
  We investigate the structure of some first terms of Watson series representing the amplitude of lepton-pair production in the ion collisions. It is shown that infrared instabilities of individual terms trend to cancel each other providing the infrared stability of whole amplitude. 
A.N. Sissakian, A.V. Tarasov, H.T. Torosyan and O.O. Voskresenskaya