Gallstone Prevalence and Risk Factors for Gallstone Disease in an Urban Population of Children and Adolescents - Kratzer, W.; Walcher, T.; Arnold, F.; Akinli, A. S.; Mason, R. A.; Denzer, C.; Böhm, B.; Imhof, A.; Hänle, M. M. (Zeitschrift für Gastroenterologie, 2010)