@misc{indiciae1822eef119d0,
  title = {Photoelectric plethysmography using reflected light.},
  author = {J NIEVEEN and W J REICHERT and L B VAN DER SLIKKE},
  year = {1956},
  doi = {10.1159/000165601},
  url = {https://pubmed.ncbi.nlm.nih.gov/13374718/},
  note = {Source identifier: 13374718}
}