Universality of the transverse momentum distributions in the framework of percolation of strings J. Dias de Deus, E. G. Ferreiro, C. Pajares and R. Ugoccioni Eur. Phys. J. C, 40 2 (2005) 229-241 Published online: 15 March 2005 DOI: 10.1140/epjc/s2005-02127-y