Two comments on the structure function approximation for deep-inelastic scattering

The mechanism of radiative return to resonance can be effectively used to describe radiative corrections in terms of the Drell-Yan process. The iteration procedure is proposed. It is shown that the y→1 kinematic region can be described in terms of modified structure functions and the Sudakov formfactor, which significantly changes the result obtained both in the lowest order and with allowance for all leading orders of perturbation theory.