@misc{indiciaefbfc191188d6,
  title = {Confounded confounding.},
  author = {W Winkelstein and L I Levin},
  year = {1981},
  doi = {10.1093/oxfordjournals.aje.a113072},
  url = {https://pubmed.ncbi.nlm.nih.gov/7457483/},
  note = {Source identifier: 7457483}
}