Textbook of Gastroenterology, by Tadataka Yamada
4th edition (May 1, 2003)
Rome II : The Functional Gastrointestinal Disorders, by Douglas A. Drossman
2nd edition (March 1, 2000)
Atlas of Gastrointestinal Endoscopy and Related Pathology, by K. Schiller
2 edition (February 1, 2002)