Foundations of Higher Mathematics: http://www.amazon.com/Foundations-Higher-Mathematics-Peter-F...
How to Solve It: http://en.wikipedia.org/wiki/How_to_Solve_It
EDIT:
Mathematical Reasoning: Writing and Proof: https://sites.google.com/site/mathematicalreasoning3ed/
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Foundations of Higher Mathematics: http://www.amazon.com/Foundations-Higher-Mathematics-Peter-F...
How to Solve It: http://en.wikipedia.org/wiki/How_to_Solve_It
EDIT:
Mathematical Reasoning: Writing and Proof: https://sites.google.com/site/mathematicalreasoning3ed/