Gödel, K. F. (1992). On formally undecidable propositions of principia mathematica and related systems. Dover.
Cita Chicago (17th ed.)Gödel, Kurt Friedrich. On Formally Undecidable Propositions of Principia Mathematica and Related Systems. Nueva York: Dover, 1992.
Cita MLA (9th ed.)Gödel, Kurt Friedrich. On Formally Undecidable Propositions of Principia Mathematica and Related Systems. Dover, 1992.
Atenció: Aquestes cites poden no estar 100% correctes.