Machado, A., Gomez, V., Panarra, A., Poças, J., Corte-Real, R., Peres, M.J., Nunes, B. and EVA Hospital Group, E.R. do 2021. Implementing an Influenza Vaccine Effectiveness Study in a Hospital Context in Portugal: The EVA Hospital Project. Acta Médica Portuguesa. 34, 1 (Jan. 2021), 20–27. DOI:https://doi.org/10.20344/amp.13438.