On the rich-club effect in dense and weighted networks V. Zlatic, G. Bianconi, A. Díaz-Guilera, D. Garlaschelli, F. Rao and G. Caldarelli Eur. Phys. J. B, 67 3 (2009) 271-275 Published online: 13 January 2009 DOI: 10.1140/epjb/e2009-00007-9