TY  - RPRT
TI  - Lever holding under free-operant avoidance.
AU  - H M Hurwitz
PY  - 1967
DO  - 10.1901/jeab.1967.10-551
UR  - https://pubmed.ncbi.nlm.nih.gov/6080834/
ID  - 6080834
ER  -