@misc{indiciaeb23108daebc5,
  title = {Causality and control: threats to internal validity.},
  author = {R Behi and M Nolan},
  doi = {10.12968/bjon.1996.5.6.374},
  url = {https://pubmed.ncbi.nlm.nih.gov/8704467/},
  note = {Source identifier: 8704467}
}