@misc{indiciae73dea2233fc8,
  title = {'Endogenous' and 'exogenous': a useful dichotomy?},
  author = {A Lewis},
  year = {1971},
  doi = {10.1017/s0033291700041817},
  url = {https://pubmed.ncbi.nlm.nih.gov/5148527/},
  note = {Source identifier: 5148527}
}