María-Victoria Belmonte Ricardo Conejo Manuel Díaz José-Luis Pérez-de-la-Cruz Coalition Formation in P2P File Sharing Systems. 153-162 2005 conf/caepia/2005 CAEPIA http://dx.doi.org/10.1007/11881216_17 db/conf/caepia/caepia2005.html#BelmonteCDP05