@misc{indiciae3f337970d9aa,
  title = {Digital heart rate meter using c.m.o.s. devices.},
  author = {A K George and A E Marble},
  year = {1981},
  doi = {10.1007/bf02441325},
  url = {https://pubmed.ncbi.nlm.nih.gov/7321625/},
  note = {Source identifier: 7321625}
}