Barnes, J., Hare, R. M., & Taylor, C. C. W. (1999). Greek philosophers: Socrates, Plato, Aristotle. Oxford University Press.

Barnes, Jonathan, R. M. Hare, and C. C. W. Taylor. Greek Philosophers: Socrates, Plato, Aristotle. Oxford: Oxford University Press, 1999.

Barnes, Jonathan, et al. Greek Philosophers: Socrates, Plato, Aristotle. Oxford University Press, 1999.