Abbas, S. S., S. Baig, S. Rafi, W. Farooq, A. Niyaz, and S. A. Amber. “Osteoporosis and Its Association With Testosterone Levels in Males in Pakistan Population”. Pakistan Journal of Medicine and Dentistry, vol. 7, no. 4, Apr. 2019, p. 5, http://ojs.zu.edu.pk/ojs/index.php/pjmd/article/view/145.