Villous adenoma in gallbladder volvulus: A rare coincidence - Gönen, Ayşe Nur; Özkan, Zeynep; Emir, Seyfi; Sarıcık, Bekir; Cihangiroğlu, Gülçin; Yazar, Fatih Mehmet; Kanat, Burhan Hakan (Turkish Journal of Gastroenterology, 2014)