TY  - RPRT
TI  - Preference for conditioned reinforcement.
AU  - B A Williams
AU  - R Dunn
PY  - 1991
DO  - 10.1901/jeab.1991.55-37
UR  - https://pubmed.ncbi.nlm.nih.gov/2002301/
ID  - 2002301
ER  -