1. An instrument for visualizing the interior of the common duct at operation;McIver;Surgery,1941
2. A new endoscopic method: the peroral choledocho-pancreatoscopy (author's transl);Kawai;Leber Magen Darm,1976
3. Endoscopic visualization of bile and pancreatic ducts;Vennes;Gastrointest Endosc,1972
4. Retrograde pancreatocholangioscopy;Takekoshi;Gastrointest Endosc,1975
5. Peroral direct cholangioscopy (PDCS) using routine straight-view endoscope: first report;Urakami;Endoscopy,1977