TY  - RPRT
TI  - Second-order optional avoidance as a function of fixed-ratio requirements.
AU  - N A Krasnegor
AU  - J V Brady
AU  - J D Findley
PY  - 1971
DO  - 10.1901/jeab.1971.15-181
UR  - https://pubmed.ncbi.nlm.nih.gov/16811498/
ID  - 16811498
ER  -