@misc{indiciae20ab54d217cc,
  title = {Observing responses and informative stimuli.},
  author = {R N Wilton and R O Clements},
  year = {1971},
  doi = {10.1901/jeab.1971.15-199},
  url = {https://pubmed.ncbi.nlm.nih.gov/16811502/},
  note = {Source identifier: 16811502}
}