DVCS on the nucleon : study of the twist-3 effects
  We estimate the size of the twist-3 effects on deeply virtual Compton scattering (DVCS) observables, in the Wandzura-Wilczek approximation. We present results in the valence region for the DVCS cross sections, charge asymmetries and single spin asymmetries, to twist-3 accuracy. 
N. Kivel, M.V. Polyakov, M. Vanderhaeghen