@misc{indiciae983fb9c51a33,
  title = {Yoked variable-ratio and variable-interval responding in pigeons.},
  author = {A C Catania and T J Matthews and P J Silverman and R Yohalem},
  year = {1977},
  doi = {10.1901/jeab.1977.28-155},
  url = {https://pubmed.ncbi.nlm.nih.gov/16812022/},
  note = {Source identifier: 16812022}
}