Wolff, R. P. (1989). About philosophy (4th ed.). Prentice Hall.
Chicagoスタイル(17版)引用形式Wolff, Robert Paul. About Philosophy. 4th ed. Englewood Cliffs, N.J: Prentice Hall, 1989.
MLA(9版)引用形式Wolff, Robert Paul. About Philosophy. 4th ed. Prentice Hall, 1989.
警告: この引用は必ずしも正確ではありません.