Self organized criticality in a modified Olami-Feder-Christensen model G. Q. Zhang, U. Tirnakli, L. Wang and T. L. Chen Eur. Phys. J. B, 82 1 (2011) 83-89 Published online: 29 June 2011 DOI: 10.1140/epjb/e2011-10941-4