Triviality of GHZ operators of higher spin
  We prove that local observables of the set of GHZ operators for particles of spin higher than 1/2 reduce to direct sums of the spin 1/2 operators $\sigma_x$, $\sigma_y$ and, therefore, no new contradictions with local realism arise by considering them. 
J. Savinien, J. Taron, R. Tarrach