TY  - RPRT
TI  - Letter: Extrinsic incentives and token-based programs. A reevaluation.
AU  - J D Ford
AU  - S L Foster
PY  - 1976
DO  - 10.1037//0003-066x.31.1.87
UR  - https://pubmed.ncbi.nlm.nih.gov/1247208/
ID  - 1247208
ER  -