Gallstone disease and obesity: a population-based study on abdominal fat distribution and gender differences oleh Amir Reza Radmard, Shahin Merat, Soheil Kooraki, Mahya Ashrafi, Abbas Keshtkar, Maryam Sharafkhah, Elham Jafari, Reza Malekzadeh, Hossein Poustchi