TY  - BOOK
AU  - Velleman,Daniel J.
TI  - How to prove it: a structured approach 
SN  - 0521675995
AV  - QA9 V444H 2006
PY  - 2006///
CY  - Cambridge
PB  - Cambridge Univ. Press
KW  - LOGIC, SYMBOLIC AND MATHEMATICAL
KW  - MATHEMATICS
N1  - Includes bibliographical references and index
ER  -