C. Coelho-Oliveira, A., B. Monteiro-Oliveira, B., B. M. Cavalcante, R., B. Santos, D., Sonza, A., C. de Sá-Caputo, D., & Bernardo-Filho, M. (2021). Vitamin D levels and risk of COVID-19 infection: A systematic review. Brazilian Journal of Health and Biomedical Sciences, 19(2), 83–90. https://doi.org/10.12957/bjhbs.2020.59708