@misc{indiciae1a391235724c,
  title = {Matching and efficiency in cohort studies.},
  author = {S Greenland and H Morgenstern},
  year = {1990},
  doi = {10.1093/oxfordjournals.aje.a115469},
  url = {https://pubmed.ncbi.nlm.nih.gov/2293747/},
  note = {Source identifier: 2293747}
}