APA (7th ed.) Citation

Smullyan, R. M. (1988). Forever undecided: A puzzle guide to Gödel. Oxford Univ. Pr.

Chicago Style (17th ed.) Citation

Smullyan, Raymond M. Forever Undecided: A Puzzle Guide to Gödel. Oxford: Oxford Univ. Pr, 1988.

MLA (9th ed.) Citation

Smullyan, Raymond M. Forever Undecided: A Puzzle Guide to Gödel. Oxford Univ. Pr, 1988.

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