@misc{indiciaef20c89f5fd1f,
  title = {Effect of verapamil on left ventricular function: a randomized, placebo-controlled study.},
  author = {R E Vlietstra and M A Farias and R L Frye and H C Smith and E L Ritman},
  year = {1983},
  doi = {10.1016/0002-9149(83)90371-5},
  url = {https://pubmed.ncbi.nlm.nih.gov/6340453/},
  note = {Source identifier: 6340453}
}