@misc{indiciaeb9aba08fcbc0,
  title = {Heart rate variability: why do spectral analysis?},
  author = {J M Karemaker},
  year = {1997},
  doi = {10.1136/hrt.77.2.99},
  url = {https://pubmed.ncbi.nlm.nih.gov/9068388/},
  note = {Source identifier: 9068388}
}