@misc{indiciae2453c8d8a344,
  title = {Matching in retrospective studies.},
  author = {R J Hardy and C White},
  year = {1971},
  doi = {10.1093/oxfordjournals.aje.a121235},
  url = {https://pubmed.ncbi.nlm.nih.gov/5543533/},
  note = {Source identifier: 5543533}
}