[maroonblazer]

To clarify:

Velleman wrote "How to Prove It": https://www.amazon.com/How-Prove-Structured-Approach-2nd/dp/...

Polya wrote "How to Solve It": https://www.amazon.com/How-Solve-Mathematical-Princeton-Scie...

[fmoralesc]

Sorry, you are right (I actually have both in front of me... and Beeler's "How to Count"). Polya is also a nice read ;)