Majority-vote model on directed Erdos-Renyi random graphs
  Through Monte Carlo Simulation, the well-known majority-vote model has been studied with noise on directed random graphs. In order to characterize completely the observed order-disorder phase transition, the critical noise parameter $q_c$, as well as the critical exponents $beta/nu$, $gamma/nu$ and $1/nu$ have been calculated as a function of the connectivity $z$ of the random graph. 
F.W.S. Lima, A.O. Sousa, M.A. Sumuor