APA (7th ed.) Citation

Smullyan, R. M. (1961). Theory of formal systems. Princeton Univ. Press.

Chicago Style (17th ed.) Citation

Smullyan, Raymond M. Theory of Formal Systems. Princeton, N.J: Princeton Univ. Press, 1961.

MLA (9th ed.) Citation

Smullyan, Raymond M. Theory of Formal Systems. Princeton Univ. Press, 1961.