TY  - RPRT
TI  - Foveal increment thresholds in protan observers.
AU  - R D Watkins
PY  - 1969
DO  - 10.1016/0042-6989(69)90109-6
UR  - https://pubmed.ncbi.nlm.nih.gov/5308024/
ID  - 5308024
ER  -