@misc{indiciae11ffc6f8d340,
  title = {Regionalization for respiratory care.},
  author = {L J Butterfield},
  year = {1973},
  doi = {10.1016/s0031-3955(16)32857-7},
  url = {https://pubmed.ncbi.nlm.nih.gov/4701224/},
  note = {Source identifier: 4701224}
}