Topological patterns in street networks of self-organized urban settlements J. Buhl, J. Gautrais, N. Reeves, R. V. Solé, S. Valverde, P. Kuntz and G. Theraulaz Eur. Phys. J. B, 49 4 (2006) 513-522 Published online: 31 March 2006 DOI: 10.1140/epjb/e2006-00085-1