APA (7th ed.) Citation

Pólya, G. (1990). How to solve it : a new aspect of mathematical method / G. Pólya ; [foreword by Ian Stewart]: A new aspect of mathematical method (2nd ed.). Penguin Books.

Chicago Style (17th ed.) Citation

Pólya, George. How to Solve It : A New Aspect of Mathematical Method / G. Pólya ; [foreword by Ian Stewart]: A New Aspect of Mathematical Method. 2nd ed. London: Penguin Books, 1990.

MLA (9th ed.) Citation

Pólya, George. How to Solve It : A New Aspect of Mathematical Method / G. Pólya ; [foreword by Ian Stewart]: A New Aspect of Mathematical Method. 2nd ed. Penguin Books, 1990.

Warning: These citations may not always be 100% accurate.