Patristic Philosophy
- Patristic Philosophy by Robert GrantEncyclopedia of Philosophy, 2nd ed.
- Patristic Philosophy by R. F. HarvanekNew Catholic Encyclopedia, 2nd ed.
- Aristotelianism by J. J. Glanville and Mark JohnsonNew Catholic Encyclopedia Supplement 2012-2013: Ethics and Philosophy
- Platonism by J. O. Riedl and M. F. WagnerNew Catholic Encyclopedia Supplement 2012-2013 : Ethics and Philosophy
- Neoplatonism by Pierre Hadot and Gary M. GurtierNew Catholic Encyclopedia Supplement 2009