TY  - BOOK
AU  - Ashlock,Robert B.
TI  - Error patterns in computation: using error patterns to improve instruction 
SN  - 0131198866
AV  - QA135.5 .A782 2006
U1  - 372.7/2044 
PY  - 2006///
CY  - Upper Saddle River, N.J.
PB  - Merrill Prentice Hall
KW  - Arithmetic
KW  - Study and teaching (Elementary)
ER  -