TY  - BOOK
AU  - Alferez, Merle S.
AU  - Cuison, Manuel., Jr.; Supangan, Guillermo S., IIi.
TI  - Mental math tricks : : addition techniques 
SN  - 971-8740-89-9
AV  - 513.213 Al28ma 
PY  - 2006///
CY  - Quezon City
PB  - MSA Publishing House
ER  -