A Prayer Before Study: Ineffable Creator
- Citation, Raccolta #764, Pius XI Studiorum Ducem, 1923.
- http://www.intervarsity.org/slj/article/2442

On the Principles of Nature
- Gerry Campbell translation.
- http://www4.desales.edu/~philtheo/aquinas/Nature.html

Aquinas on Law
- Selections from the Summa Theologiae pertaining to law, translated by David Burr. "Responsio" sections only, some articles omitted entirely. From I-II, 90, 1, to I-II, 97, 2.
- http://www.fordham.edu/halsall/source/aquinas2.html

On the Eternity of the World
- Robert T. Miller translation. "We thus ought to determine whether there is any contradiction between these two ideas, namely, to be made by God and to have always existed." At the Internet Medieval Sourcebook.
- http://www.fordham.edu/halsall/basis/aquinas-eternity.html

Summa Theologica
- Complete text of the 1947 Benziger Brothers edition, with concordances and word frequency lists. Each question in its own file.
- http://www.intratext.com/X/ENG0023.htm

On the Mixture of the Elements, to Master Philip of Castrocaeli
- Paul Vincent Spade translation. In pdf. 111K.
- http://pvspade.com/Logic/docs/mixture.pdf

Of God and His Creatures
- An annotated, abridged version of St. Thomas Aquinas's work "Summa Contra Gentiles". At Notre Dame.
- http://www.nd.edu/Departments/Maritain/etext/gc.htm