How Read and Do Proofs: An Introduction to Mathematical Thought Processes - Solow, Daniel (New York John Wiley & Sons, Inc., 1990)
The Truth of It The Forward-Backward Method On Definitions and Mathematical Terminology Quantifiers I: The Construction Method Quantifiers II: The Choose Method Quantifiers III: Induction Quantifiers IV: Specialization Quantifiers V: Nested Quantifiers The Contradiction Method The Contrapositive Method Nots of Nots Lead to Knots Special Proof Techniques