@misc{indiciae8b29d8b27557,
  title = {Pulsed multifrequency photoplethysmograph.},
  author = {J Giltvedt and A Sira and P Helme},
  year = {1984},
  doi = {10.1007/bf02442745},
  url = {https://pubmed.ncbi.nlm.nih.gov/6738126/},
  note = {Source identifier: 6738126}
}