Cita APA (7th ed.)
Allen, L. E. (1970). WFF'N PROOF: THE GAME OF MODERN LOGIC.
Cita Chicago (17th ed.)
Allen, Layman E. WFF'N PROOF: THE GAME OF MODERN LOGIC. 1970.
Cita MLA (9th ed.)
Allen, Layman E. WFF'N PROOF: THE GAME OF MODERN LOGIC. 1970.
Atenció: Aquestes cites poden no estar 100% correctes.