1. Department of Economic Studies, University of Chieti-Pescara, viale Pindaro 42, 65127 Pescara, Italy
2. Department of Economic Studies and INdAM Local Unit, University of Chieti-Pescara, viale Pindaro 42, 65127 Pescara, Italy
3. RBC Capital Markets, London, UK
4. School of Engineering, UCBM, via Alvaro del Portillo, 21, 00128 Rome, Italy