TY  - BOOK
AU  - Van de Walle, John A.
AU  -  John A.Van de Walle
TI  - Elementary  and middle school mathematics: teaching developmentally 
SN  - 0205483925
AV  - QA 135.6.V36 2007 
PY  - 2007///
CY  - Boston
PB  - Pearson
KW  - Mathematics-Study and teaching(Elementary)
ER  -