TY  - RPRT
TI  - Duodenoscopy: methods and findings.
AU  - M Classen
AU  - H Koch
AU  - L Demling
PY  - 1971
DO  - 10.1016/s0016-5107(71)74035-8
UR  - https://pubmed.ncbi.nlm.nih.gov/5129979/
ID  - 5129979
ER  -