RT Journal Article SR Electronic T1 Epidemiological evidence for the association of aspirin and acute gastrointestinal bleeding. JF Gut JO Gut FD BMJ Publishing Group Ltd and British Society of Gastroenterology SP 627 OP 634 DO 10.1136/gut.11.7.627 VO 11 IS 7 A1 M J Langman YR 1970 UL http://gut.bmj.com/content/11/7/627.abstract AB