1Thomas Aquinas, Summa Theologica , I - II,q. 94 ,a. 2, translated by the Fathers of the English Dominican Province, New York, Benziger Brothers, 1948.
3Thomas Aquinas, De Veritate, q. 8, a. 6, c. , translated by Robert W. M, Mulligan, Indianapolis/Cambridge: Hackett Publishing Company, Inc, 1994.
4Thomas Aquinas, Summa Contra Gentiles, I, ch. 77 ; ch. 3, translated by Anton C. Pegis, F. R. S. C, Notre Dame, London: University of Notre Dame Press, 1975.
5Thomas Aquinas, De Veritate, q. 10,a. 6,ad. 2;q. 10,a. 6,ad. 7,translated by James V. McGlynn, Indianapolis/Cambridge: Hackett Publishing Company, Inc, 1994.
6F. C. Copleston: Aquinas, Baltimore, Maryland: Penguin Books, 1955, p. 26.
7Thomas Aquinas, Summa Theologica,I,q. 78,a. 3.
8Thomas Aquinas, Summa Theologica,I,q. 85 ,a. 1,ad. 3.
9Thomas Aquinas, De Spiritualibus Creaturis, a. 9, ad. 6, translated by Mary C. FitzPatrick , Ph. D and John J. Wellmuth, Ph. D, Milwaukee, Wisconsin: The Marquette University Press, 1949.
