Smullyan, R. M. (1995). First-order logic. Dover.
Cita Chicago (17th ed.)Smullyan, Raymond M. First-order Logic. Nueva York: Dover, 1995.
Cita MLA (9th ed.)Smullyan, Raymond M. First-order Logic. Dover, 1995.
Atenció: Aquestes cites poden no estar 100% correctes.