Exclusive electroproduction and the quark structure of the nucleon
  The natural interpretation of deep inelastic scattering is in terms of hard scattering on QCD constituents of the target. We examine the relation between amplitudes measured in exclusive lepto-production and the quark content of the nucleon. We show that in the Bjorken limit, the natural interpretation of amplitudes measured in these hard exclusive processes is in terms of the quark content of the meson cloud and not the target itself. Therefore the most efficient representation of these exclusive processes is in terms of leading Regge amplitudes. 
Adam P. Szczepaniak and J.T. Londergan