@misc{indiciae9a1a410623f6,
  title = {Pacemaker sound and its origin.},
  author = {W F Kluge},
  year = {1970},
  doi = {10.1016/s0002-9149(70)80017-0},
  url = {https://pubmed.ncbi.nlm.nih.gov/5438990/},
  note = {Source identifier: 5438990}
}