ÇETİNKAYA, Hülya, et al. “BENIGN PNEUMOPERITONEUM AND SUBCUTANEOUS EMPHYSEMA DUE TO THERAPEUTIC COLONOSCOPY”. Turkish Journal of Gastroenterology, vol. 4, no. 4, Jan. 1993, pp. 713-5, https://turkjgastroenterol.org/index.php/tjg/article/view/344.