TY  - RPRT
TI  - Gradients as visual primitives.
AU  - B Goodenough
AU  - B Gillam
PY  - 1997
DO  - 10.1037//0096-1523.23.2.370
UR  - https://pubmed.ncbi.nlm.nih.gov/9104000/
ID  - 9104000
ER  -