Khoiroh, M., Atmaka, D., & Ayuningtyas, P. (2021). Effectiveness of vitamin D-based therapy in reducing clinical impact of Covid-19 patients: A systematic review. Romanian Journal of Diabetes Nutrition and Metabolic Diseases, 28(3), 331-336. Retrieved from https://rjdnmd.org/index.php/RJDNMD/article/view/1031