Monte Carlo simulation of Ising model on directed Barabasi-Albert   network
  The existence of spontaneous magnetization of Ising spins on directed Barabasi-Albert networks is investigated with seven neighbors, by using Monte Carlo simulations. In large systems we see the magnetization for different temperatures T to decay after a characteristic time tau, which is extrapolated to diverge at zero temperature. 
Muneer A. Sumour and M.M. Shabat