Lipman, M. (1977). Discovering philosophy (2nd edition.). Prentice- Hall Inc..
Chicago Edition CitationLipman, Mathew. Discovering Philosophy. 2nd edition. New Jersey: Prentice- Hall Inc., 1977.
Cita MLALipman, Mathew. Discovering Philosophy. 2nd edition. Prentice- Hall Inc., 1977.
Atenció: Aquestes cites poden no estar 100% correctes.