Peter B. Cotton & Christopher B. Williams 
Practical Gastrointestinal Endoscopy [PDF ebook] 
The Fundamentals

Practical Gastrointestinal Endoscopy has become the basic primer for endoscopy around the world. This new edition has been thoroughly revised and updated. Drawing on the vast experience of the authors it provides clear and practical guidance on the fundamentals of standard endoscopy practice. It describes procedures in great depth and addresses improved therapeutic techniques and advances in technology. The book is well illustrated throughout with color line drawings and diagrams. It is an indispensable resource for all trainees in gastroenterology and essential read for all practising endoscopists who are interested in improving their techniques.