TY  - BOOK
AU  - Velleman,Daniel J.
TI  - How to prove it: a structured approach
SN  - 0521861241
PY  - 2006///
CY  - Cambridge, New York
PB  - Cambridge University Pressc2006.
KW  - LÃ³gica simbÃ³lica y matemÃ¡tica
KW  - MatemÃ¡ticas
KW  - Funciones
ER  -