@misc{indiciae734ebc46bcd9,
  title = {Gas mixtures for calibration.},
  author = {E J Campbell and H M Pope},
  year = {1968},
  doi = {10.1136/bmj.3.5618.617},
  url = {https://pubmed.ncbi.nlm.nih.gov/5668002/},
  note = {Source identifier: 5668002}
}