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2. Anselm, Monologion. trans. Thomas Williams. Indianapolis: Hackett Publishing, 1995.
3. Aquinas. Summa Theologica. trans. Fathers of the English Dominican Province. Benziger Brothers Edition, 1947. Retrieved from www.gutenberg.org/cache/epub/17611/pg17611-images.html on 13.05.2020.
4. Aspell, Patrick J. Medieval Western Philosophy: The European Emergence. Washington DC: The Council for Research in Values and Philosophy, 1999.
5. Augustine. Against the Academics. trans. and ann. John J. O'meara. New York: Newman Press, 1951.