1. Department of Industrial and Information Engineering and of Economics, University of L'Aquila, Piazzale Ernesto Pontieri, Monteluco di Roio, 67100 L'Aquila, Italy
2. Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, Coste Sant'Agostino Campus, Via R. Balzarini, 1, 64100 Teramo (TE), Italy