1. Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
2. Division of Gastroenterology and Hepatology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
3. Department of Medicine, Johns Hopkins Bayview Medical Center, Baltimore, Maryland, USA
4. Galter Health Sciences Library, Northwestern University Feinberg School of Medicine, Chicago, Illinois