@misc{indiciae1c5f21072919,
  title = {Letter: Electrocardiogram interpretation.},
  author = {W J Walker},
  year = {1973},
  doi = {10.1001/jama.226.11.1361b},
  url = {https://pubmed.ncbi.nlm.nih.gov/4800774/},
  note = {Source identifier: 4800774}
}