RT Journal Article SR Electronic T1 Cholelithiasis: causes and treatment JF Gut JO Gut FD BMJ Publishing Group Ltd and British Society of Gastroenterology SP 859 OP 859 DO 10.1136/gut.41.6.859-c VO 41 IS 6 A1 K HEATON YR 1997 UL http://gut.bmj.com/content/41/6/859.3.abstract AB