1. Department of Economics and Management, University of Pisa, Via Cosimo Ridolfi 10, 56124 Pisa, Italy
2. Department of Law, University of Genoa, Via Balbi 30/19, 16126 Genoa, Italy
3. Department of Economics and Law, University of Macerata, Via Crescimbeni 20, 62100 Macerata, Italy