@misc{indiciae19496cbb7537,
  title = {Conditioned reinforcement in second-order schedules.},
  author = {R T Kelleher},
  year = {1966},
  doi = {10.1901/jeab.1966.9-475},
  url = {https://pubmed.ncbi.nlm.nih.gov/5964502/},
  note = {Source identifier: 5964502}
}