A-S. U, et.al, D. H. “Physiological Harmony of Hormones Related to the Thyroid Gland Function in Cretinous Sheep”. Al-Qadisiyah Journal of Pure Science, Vol. 20, no. 2, July 2017, pp. 1-13, https://journalsc.qu.edu.iq/index.php/JOPS/article/view/66.