@misc{indiciaeb1cadaac9d56,
  title = {Twenty years on.},
  author = {M Shepherd},
  year = {1990},
  doi = {10.1017/s0033291700013167},
  url = {https://pubmed.ncbi.nlm.nih.gov/2320687/},
  note = {Source identifier: 2320687}
}