1. Gastroenterology and Hepatology, University of Nebraska Medical Center, Omaha, Nebraska, United States
2. Internal Medicine, University of Arizona, Banner University Medical Center, Tucson, Arizona, United States
3. Boston University Medical Center, Boston, Massachusetts, United States
4. Gastroenterology & Hepatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States
5. Internal Medicine, University of Toledo, Ohio, United States
6. University Library, University of Toledo, Ohio, United States
7. Internal Medicine, Carilion Roanoke Memorial Hospital, Roanoke, Virginia, United States