Murad, R., T. Mahboob, R. Rehman, and R. Baig. “Comparison of Serum Levels of Vitamin D and Vitamin D-Binding Protein in Normal, Osteopenic and Osteoporotic Postmenopausal Women: Vitamin D and Vitamin D-Binding Proteins in Post Menopausal Females”. Pakistan Journal of Medical Sciences, Vol. 35, no. 2, Mar. 2019, doi:10.12669/pjms.35.2.714.