@misc{indiciae3b5a6b249bf1,
  title = {First degree AV block.},
  author = {R G Co},
  year = {1968},
  doi = {10.1378/chest.54.6.557},
  url = {https://pubmed.ncbi.nlm.nih.gov/5722776/},
  note = {Source identifier: 5722776}
}