@misc{indiciaeb30637a6ba81,
  title = {What is a control group?},
  author = {L Hartmann},
  year = {1992},
  doi = {10.1097/00004583-199207000-00033},
  url = {https://pubmed.ncbi.nlm.nih.gov/1644744/},
  note = {Source identifier: 1644744}
}