Khan, A., M. Zubair, S. Khan, U. khalid, K. Sultan, and M. K. Khan. “The Role of Vitamin D Deficiency and Supplementation in Onset and Progression of Diabetic Nephropathy: A Systematic Review”. Romanian Journal of Diabetes Nutrition and Metabolic Diseases, Vol. 29, no. 1, Mar. 2022, pp. 135-54, http://rjdnmd.org/index.php/RJDNMD/article/view/1093.