@misc{indiciae5b59f9c2feb7,
  title = {Notes on respiratory performance during labour.},
  author = {J S Crawford and M E Tunstall},
  year = {1968},
  doi = {10.1093/bja/40.8.612},
  url = {https://pubmed.ncbi.nlm.nih.gov/5667306/},
  note = {Source identifier: 5667306}
}