TY  - RPRT
TI  - Some difficulties with difficulty: note on Horst's "Mattrix Factoring and Test Theory".
AU  - M C Corballis
PY  - 1968
DO  - 10.2466/pr0.1968.22.1.15
UR  - https://pubmed.ncbi.nlm.nih.gov/5641202/
ID  - 5641202
ER  -