Duality for finite Hopf algebras explained by corings
  We give a coring version for the duality theorem for actions and coactions of a finitely generated projective Hopf algebra. We also provide a coring analogue for a theorem of H.-J. Schneider, which generalizes and unifies the duality theorem for finite Hopf algebras and its refinements. 
S. Caenepeel, D. Quinn and S. Raianu