Giansante, C. et al. 2021. COVID-19 vaccine effectiveness among the staff of the Bologna Health Trust, Italy, December 2020-April 2021. Acta Biomedica Atenei Parmensis. 92, 4 (Sep. 2021), e2021270. DOI:https://doi.org/10.23750/abm.v92i4.11896.