@misc{indiciaee1d732e7efa7,
  title = {Causal effect questioned.},
  author = {M S Amstey},
  year = {1990},
  doi = {10.1016/0002-9378(90)91034-a},
  url = {https://pubmed.ncbi.nlm.nih.gov/2156427/},
  note = {Source identifier: 2156427}
}