@misc{indiciaee8a83fe2623c,
  title = {Occult-blood tests.},
  author = {R G Simpson},
  year = {1970},
  doi = {10.1016/s0140-6736(70)91126-8},
  url = {https://pubmed.ncbi.nlm.nih.gov/4191916/},
  note = {Source identifier: 4191916}
}