TY  - RPRT
TI  - Combination and structure, not gradedness, is the issue.
AU  - Steven Pinker
AU  - Michael Ullman
PY  - 2002
DO  - 10.1016/s1364-6613(02)02013-2
UR  - https://pubmed.ncbi.nlm.nih.gov/12457898/
ID  - 12457898
ER  -