Barbalho, s., 		Sloan, K., 		Sloan, L., 		Goulart, R., 		Quesada, K., 		Laurindo, L., 		Zutin, T., & 		Bechara, M.
2022 Jun 27.  Effects of Vitamin D in the Prophylaxis and Treatment of COVID-19: A Systematic Review. Medical Research Archives. [Online] 10:6