APA (7th ed.) Citation

Wolff, R. P., & Vengrin, M. (1998). About philosophy: Study guide (7η έκδ.). Prentice Hall.

Chicago Style (17th ed.) Citation

Wolff, Robert Paul, and Michael Vengrin. About Philosophy: Study Guide. 7η έκδ. Upper Saddle River, N.J.: Prentice Hall, 1998.

MLA (8th ed.) Citation

Wolff, Robert Paul, and Michael Vengrin. About Philosophy: Study Guide. 7η έκδ. Prentice Hall, 1998.