Effective ”short” double-balloon enteroscope for diagnostic and therapeutic ERCP in patients with altered gastrointestinal anatomy: a large case series - Shimatani, M.; Matsushita, M.; Takaoka, M.; Koyabu, M.; Ikeura, T.; Kato, K.; Fukui, T.; Uchida, K.; Okazaki, K. (Endoscopy, 2009)