Farias, Eliana dos Santos, Dayana Ferraz Silva, Valdir Silva da Conceição, and Angela Machado Rocha. “Vitamin D As an Immunological Factor in Combating COVID-19”. International Journal of Advanced Engineering Research and Science 7, no. 6 (June 9, 2020). Accessed July 22, 2024. https://journal-repository.com/index.php/ijaers/article/view/2067.