Sadat Afjeh, Seyedeh Niki, Nahal Emami Fard, and Paniz Poursharif. “The Implications of Vitamin D Levels in COVID-19 Morbidity and Mortality”. Sciential - McMaster Undergraduate Science Journal 1, no. 5 (December 4, 2020): 2–3. Accessed March 28, 2024. https://journals.mcmaster.ca/sciential/article/view/2548.