Baig, M. A. ., S. M. . Humail, M. Iqbal, and N. ul . Islam. “Serum Vitamin D in Common Non-Metabolic Disorders: Results of Patients’ Survey at Public Hospitals of Karachi”. Journal of the Dow University of Health Sciences (JDUHS), vol. 3, no. 3, Dec. 2009, pp. 114-20, https://jduhs.jduhs.duhs.edu.pk/index.php/jduhs/article/view/1343.