@misc{indiciae44132a690301,
  title = {Heart rate calculator.},
  author = {Y C Lin and S M Horvath},
  year = {1969},
  doi = {10.1152/jappl.1969.27.4.564},
  url = {https://pubmed.ncbi.nlm.nih.gov/5822566/},
  note = {Source identifier: 5822566}
}