Premessa
Language: it
Copyright © 2018 Carlo Bagnoli, Alessia Bravin, Maurizio Massaro, Alessandra Vignotto. This is an open-access work distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction is permitted, provided that the original author(s) and the copyright owner(s) are credited and that the original publication is cited, in accordance with accepted academic practice. The license allows for commercial use. No use, distribution or reproduction is permitted which does not comply with these terms.