APA (7th ed.) Citation

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

Chicago Style (17th ed.) Citation

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

MLA (8th ed.) Citation

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