1. Practical gastrointestinal endoscopy;Cotton,1990
2. Endoscopic papillotomy;Classen,1987
3. Duodenoscopic sphincterotomy and gallstone removal;Safrany;Gastroenterology,1977
4. Endoscopic retrograde sphincterotomy;Silvis,1984
5. Precurved papillotomes vs. the standard type papillotomes: the evolution of a true 12 o'clock technology;Noar;Gastrointest Endosc,1994