Zaporozhchenko, B., V. Kolodiy, A. Gorbunov, P. Muraviov, and D. Bondarec. “Differentiated Approach to a Method Choosing of Complicated Gallstone Disease Treatment in Patients of Older Age Groups”. Reports of Vinnytsia National Medical University, Vol. 21, no. 1(1), Sept. 2017, pp. 125-9, https://reports-vnmedical.com.ua/index.php/journal/article/view/94.