@misc{indiciaed2c22656db22,
  title = {Reinforcement delay: some effects on behavioral contrast.},
  author = {R W Richards},
  year = {1972},
  doi = {10.1901/jeab.1972.17-381},
  url = {https://pubmed.ncbi.nlm.nih.gov/16811595/},
  note = {Source identifier: 16811595}
}