8Tom Beauchamp. Principle of Biomedical Ethics, Fifth Edition, New York: Oxford University Press, 2001.
9Philippa Foot. Virtues and Vices and Other Essays in Moral Philosophy, Berkeley and Los Angeles: University of California Press, 1978.
10Martha Nussbaum. "Non - Relative Virtues : An Aristotelian Approach," in The Quality of Life, Martha Nussbaum and Amartya Sen, ed. Oxford: Clarendon Press, 1993.
