Taciser Kaya, et al. “Serum Levels of (25) 0H Vitamin-D and Hyperparathyroidism in Healthy Postmenopausal Women”. Archives of Rheumatology, vol. 22, no. 1, Mar. 2007, pp. 020-3, http://anadolupsikiyatri.net/index.php/pub/article/view/214.