TY  - RPRT
TI  - ACQUISITION AND EXTINCTION AFTER INITIAL TRIALS WITHOUT REWARD.
AU  - N E SPEAR
AU  - W F HILL
AU  - D J O'SULLIVAN
PY  - 1965
DO  - 10.1037/h0021628
UR  - https://pubmed.ncbi.nlm.nih.gov/14256243/
ID  - 14256243
ER  -