TY  - RPRT
TI  - Environmental determinants of basic difficulty problems.
AU  - A J DRUCKER
AU  - H H REMMERS
PY  - 1952
DO  - 10.1037/h0062798
UR  - https://pubmed.ncbi.nlm.nih.gov/14937977/
ID  - 14937977
ER  -