@misc{indiciae8b8c5ec61867,
  title = {Effect of punishment on human variable-interval performance.},
  author = {C M Bradshaw and E Szabadi and P Bevan},
  year = {1977},
  doi = {10.1901/jeab.1977.27-275},
  url = {https://pubmed.ncbi.nlm.nih.gov/16811989/},
  note = {Source identifier: 16811989}
}