Porycka, Urszula, et al. “Surgical Management of Cholecystoduodenal Fistula Complicated by Ileus (Mirizzi Syndrome Type Vb). A Case Report”. Annali Italiani Di Chirurgia, vol. 10, no. April, Apr. 2021, pp. 1-5, https://annaliitalianidichirurgia.it/index.php/aic/article/view/771.