Ray-Offor, Emeka, and Christopher Obiorah. “Upper Gastro-Intestinal Endoscopy in Port-Harcourt: An Audit”. The Nigerian Health Journal 13, no. 4 (December 13, 2015): 192. Accessed November 21, 2024. https://tnhjph.com/index.php/tnhj/article/view/119.