TY  - BOOK
AU  - POLYA,G
TI  - How To Solve It: : The Classic Introduction to Matematical Problem-Solving with a Foreword by Ian Stewart 
U1  - 510. 
PY  - 1945///
CY  - London
PB  - Penguin Books
KW  - 0
KW  - Grade 10-12
ER  -