@misc{indiciaebde146f48073,
  title = {Duodenoscopy: methods and findings.},
  author = {M Classen and H Koch and L Demling},
  year = {1971},
  doi = {10.1016/s0016-5107(71)74035-8},
  url = {https://pubmed.ncbi.nlm.nih.gov/5129979/},
  note = {Source identifier: 5129979}
}