TY  - BOOK
AU  - Richardson,Kathy
TI  - Developing number concepts using unifix cubes
SN  - 0201061171
AV  - QA141.15 .R53 1984
U1  - 513.2 22nd ed.
PY  - 1984///
CY  - California
PB  - Addison-Wesley Publishing Company
KW  - Number concept
ER  -