Tartaglia, Dario, et al. “A Delayed Conversion May Increase the Risk of Major Complications in Acute Cholecystitis Approached Laparoscopically. A Retrospective Comparative Cohort Study”. Annali Italiani Di Chirurgia, vol. 90, no. 3, May 2019, pp. 213-9, https://annaliitalianidichirurgia.it/index.php/aic/article/view/1220.