@misc{indiciae2f54368ac2cc,
  title = {Oxygen warning device.},
  author = {C S Ward},
  year = {1968},
  doi = {10.1093/bja/40.11.907},
  url = {https://pubmed.ncbi.nlm.nih.gov/5704360/},
  note = {Source identifier: 5704360}
}