@misc{indiciaec39f5a3b8381,
  title = {Endoscopy: why and when.},
  author = {R Johnsen},
  year = {1990},
  doi = {10.3109/02813439008994955},
  url = {https://pubmed.ncbi.nlm.nih.gov/2284515/},
  note = {Source identifier: 2284515}
}