Bibliography - Sources

- H. Enderton, A mathematical introduction to logic, New York : Academic Press, 1972.

- G. Metakides, Principles of logic and logic programming, Elsevier Science, 1996.

- C. Allen, M. Hand, Logic Primer, Cambridge, Mass. : MIT Press, c2001.

- C. Chang and R. Lee, Symbolic Logic and Mechanical Theorem Proving, Academic Press, 1997.