Institution: | 1. Department of Economics and Finance, University of Rome Tor Vergata, Rome, Italy.;2. benedett@unich.it Department of Economic Studies, University ‘G. d’Annunzio’ of Chieti-Pescara, Pescara, Italy.;3. postigli@unich.it Department of Economic Studies, University ‘G. d’Annunzio’ of Chieti-Pescara, Pescara, Italy. |