Wolff, R. P. (1981). About philosophy: About philosophy (2nd ed.). Prentice-Hall.
Chicago Style (17th ed.) CitationWolff, Robert Paul. About Philosophy: About Philosophy. 2nd ed. Englewood Cliffs, NJ: Prentice-Hall, 1981.
MLA (9th ed.) CitationWolff, Robert Paul. About Philosophy: About Philosophy. 2nd ed. Prentice-Hall, 1981.
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