@misc{indiciaec1055c64b70d,
  title = {A twin study.},
  author = {O W Hill},
  year = {1968},
  doi = {10.1192/bjp.114.507.175},
  url = {https://pubmed.ncbi.nlm.nih.gov/5640458/},
  note = {Source identifier: 5640458}
}