1. Aristotle. (1999). Nicomachean ethics (T. Irwin, Trans.). 2nd ed. Indianapolis, IN: Hackett.
2. Augustine. (1993). On free choice of the will (T. Williams, Trans.). Indianapolis, IN: Hackett.
3. Augustine. (1997). Answer to the Pelagians (R.J. Teske, Trans.). Hyde Park, NY: New City.
4. Augustine. (1999). Answer to the Pelagians, IV (R.J. Teske, Trans.). Hyde Park, NY: New City.
5. Augustine. (2006). Confessions (F.J. Sheed, Trans.). 2nd ed. Indianapolis, IN: Hackett.