@misc{indiciaed69de6c4d88b,
  title = {Fixed-interval punishment.},
  author = {J B Appel},
  year = {1968},
  doi = {10.1901/jeab.1968.11-803},
  url = {https://pubmed.ncbi.nlm.nih.gov/16811326/},
  note = {Source identifier: 16811326}
}