Penrose, R. (1999). The large, the small and the human mind. Univ. Pr..
Cita Chicago (17th ed.)Penrose, Roger. The Large, the Small and the Human Mind. Cambridge: Univ. Pr., 1999.
Cita MLA (9th ed.)Penrose, Roger. The Large, the Small and the Human Mind. Univ. Pr., 1999.
Atenció: Aquestes cites poden no estar 100% correctes.