1. Division of Gastroenterology, University of California-San Francisco, San Francisco, CA, USA
2. Department of Gastroenterology, Hepatology and Nutrition, University of Texas MD Anderson Cancer Center, Houston, TX, USA
3. Mulford Health Sciences Library, University of Toledo, Toledo, OH, USA
4. Department of Medicine, University of Toledo, Toledo, OH, USA
5. Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
6. Department of Medicine, Loyola Medicine/MacNeal Hospital, Berwyn, IL, USA
7. Division of Gastroenterology, William Beaumont Hospital, Royal Oak, MI, USA
8. Division of Gastroenterology, University of Tennessee Health Science Center, Memphis, TN, USA