Major sports events and the transmission of SARS-CoV-2: analysis of seven case-studies in Europe - Signorelli, C.; Odone, A.; Riccò, M.; Bellini, L.; Croci, R.; Oradini-Alacreu, A.; Fiacchini, D.; Burioni, R. (Acta bio-medica: Atenei Parmensis, 2020)