Generalized quantum measurements and local realism
  The structure of a local hidden variable model for experiments involving sequences of measurements rigorously is analyzed. Constraints imposed by local realism on the conditional probabilities of the outcomes of such measurement schemes are explicitly derived. The violation of local realism in the case of ``hidden nonlocality'' is illustrated by an operational example. 
Marek Zukowski, Ryszard Horodecki, Michal Horodecki and Pawel   Horodecki