@misc{indiciaebd0353972967,
  title = {Real-time two-dimensional echocardiography.},
  author = {D J Sahn},
  year = {1981},
  doi = {10.1016/s0022-3476(81)80446-5},
  url = {https://pubmed.ncbi.nlm.nih.gov/7019403/},
  note = {Source identifier: 7019403}
}