Application and usefulness of a new eight‐wire basket catheter for endoscopic extraction of small common bile duct stones: A retrospective multicenter study oleh Osamu Inatomi, Masanobu Katayama, Koichi Soga, Takashi Yamamoto, Takao Mikami, Yukihiro Morita, Jun Nakajima, Shuhei Shintani, Yuki Yagi, Yuki Kishi, Kazuyoshi Matsumura