@misc{indiciaeccf82cbd2856,
  title = {Electrophysiological testing of sinus node function.},
  author = {A M Tonkin and W F Heddle},
  year = {1984},
  doi = {10.1111/j.1540-8159.1984.tb05604.x},
  url = {https://pubmed.ncbi.nlm.nih.gov/6205377/},
  note = {Source identifier: 6205377}
}