Kuchin, Yu. L., K. Yu. Byelka, and V. P. Babych. “Predictors of Severe Postoperative Pain in Patients After Laparoscopic Cholecystectomy”. Klinicheskaia khirurgiia0, no. 8 (September 7, 2017): 24-26. Accessed September 30, 2020. https://hirurgiya.com.ua/index.php/journal/article/view/195.