Polya

How to Solve It: A New Aspect of Mathematical Method

By Polya, George

Mathematics and Plausible Reasoning, Volume II: Patterns of Plausible Inference

By Polya, G.

How to Solve It: A New Aspect of Mathematical Method (Princeton Science Library)

By Polya, G., Conway, John H.

Mathematical Discovery Combined Ed: On Understanding, Learning, and Teaching Problem Solving

By Polya, George