@misc{indiciae90d69836f324,
  title = {Letter: Propranolol and digitalis.},
  author = {M H Crawford and M LeWinter and J S Karliner and R A O'Rourke},
  year = {1974},
  doi = {10.1016/s0140-6736(74)92416-7},
  url = {https://pubmed.ncbi.nlm.nih.gov/4131461/},
  note = {Source identifier: 4131461}
}