American Gastroenterological Association Web Site
American Society for Gastrointestinal Endoscopy
Colon Cancer Alliance – Prevention & Screening
Colon Cancer Alliance – Statistics
Columbia University – Gastroenterological Diseases
Columbia University – Diseases of the Liver
Crohn’s & Colitis Foundation of America, Inc.
Internet Public Library – Health & Medical Sciences
MEDLINEplus – Health Database maintained by NIH Lib of Medicine
Merck Manual of Diagnosis and Therapy
NIDDK Health Information – Digestive Diseases
The Northwestern Society of Intestinal Research
PubMed – Database of Articles from the National Institute of Health