@misc{9521, author = {C. Crooks and T. Card and J. West}, title = {Defining upper gastrointestinal bleeding from linked primary and secondary care data and the effect on occurrence and 28 day mortality}, year = {2012}, journal = {BMC Health Serv Res}, volume = {12}, pages = {392}, issn = {1472-6963}, doi = {10.1186/1472-6963-12-392}, }