APA (7th ed.) Citation

Ayer, A. J., & O'Grady, J. (1994). A dictionary of philosophical quotations. Blackwell Publishers.

Chicago Style (17th ed.) Citation

Ayer, A. J., and Jane O'Grady. A Dictionary of Philosophical Quotations. Oxford, UK ; Cambridge, MA, USA: Blackwell Publishers, 1994.

MLA (8th ed.) Citation

Ayer, A. J., and Jane O'Grady. A Dictionary of Philosophical Quotations. Blackwell Publishers, 1994.