  Urmson, J. O. (1988) Aristotle's Ethics.
<meaning-changed>   Urmson, J. O. (1988) Aristotle's Ethics.
 Plato. Plato's Complete Works, John M. Cooper, ed. Translated by D. S. Hutchinson. Indianapolis: Hackett Publishing Co., 1997. Urmson, J. O. (1988) Aristotle's Ethics.