Why prove it again? [electronic resource] : alternative proofs in mathematical practice / John W. Dawson, Jr., with the assistance of Bruce S. Babcock and with a chapter by Steven H. Weintraub.

Proofs in Mathematical Practice
Motives for Finding Alternative Proofs
Sums of Integers
Quadratic Surds
The Pythagorean Theorem
The Fundamental Theorem of Arithmetic
The Infinitude of the Primes
The Fundamental Theorem of Algebra
Desargues's Theorem
The Prime Number Theorem
The Irreducibility of the Cyclotomic Polynomials
The Compactness of First-Order Languages
Other Case Studies.