@misc{indiciaebd9ec5629e3d,
  title = {Contingency management: schedule effects.},
  author = {John M Roll and Steve Shoptaw},
  year = {2006},
  doi = {10.1016/j.psychres.2005.12.003},
  url = {https://pubmed.ncbi.nlm.nih.gov/16905197/},
  note = {Source identifier: 16905197}
}