TY  - DATA
AU  - Wu, Hongxi
TI  - Understanding numbers in elementary school mathematics 
T2  - Miscellaneous Books, 
SN  - 9781470412104 (online)
PY  - 2011///
CY  - Providence, R.I.
PB  - American Mathematical Society
KW  - Mathematics
KW  - Number concept
N1  - Includes bibliographical references and index
UR  - https://doi.org/10.1090/mbk/079
ER  -