Pablo Revilla University Pablo de Olavide, Sevilla.   Department of Economics. Universidad Pablo de Olavide. Ctra. de Utrera km 1. Sevilla, Sevilla E-41013 Spain   prevapa@dee.upo.es         Primary Research Focus: Coalition Formation, Matching Theory, Public Goods, Implementation.   JEL Areas: C7 : Game Theory and Bargaining Theory:General D0 : Microeconomics: General