| Agnellus of Ravenna | The Book of Pontiffs of the Church of Ravenna |
| P. H. Ahearn | The Catholic University of America, 1887-1896 |
| G Alberigo eds | The Reception of Vatican II |
| Albert the Great | Questions concerning Aristotle's On Animals |
| Saint Ambrose | Letters, 1-91 |
| Saint Ambrose | Hexameron, Paradise, Cain and Abel |
| Saint Ambrose | Theological and Dogmatic Works |
| Saint Ambrose | Seven Exegetical Works |
| Thomas Aquinas | Commentaries on Aristotle's "On Sense and What Is Sensed" and "On Memory and Recollection" |
| Thomas Aquinas | An Exposition of the On the Hebdomads of Boethius |
| Thomas Aquinas | Commentary on the Book of Causes |
| Thomas Aquinas | On Love and Charity: Readings from the "Commentary on the Sentences of Peter Lombard" |
| Frederick D. Aquino | Communities of Informed Judgment |
| Benedict M. Ashley | Justice in the Church |
| Nigel Aston | Religion and Revolution in France, 1780-1804 |
| Johann Auer | The Church |
| Johann Auer | A General Doctrine of the Sacraments and The Mystery of the Eucharist |
| Saint Augustine | Christian Instruction; Admonition and Grace; The Christian Combat; Faith, Hope and Charity |
| Saint Augustine | The City of God, Books VIII-XVI |
| Saint Augustine | Letters, Volume 1 (1-82) |
| Saint Augustine | Commentary on the Lord's Sermon on the Mount with Seventeen Related Sermons |
| Saint Augustine | The City of God, Books I-VII |
| Saint Augustine | The Immortality of the Soul; The Magnitude of the Soul; On Music; The Advantage of Believing; On Faith in Things Unseen |
| Saint Augustine | Treatises on Various Subjects |
| Saint Augustine | The City of God, Books XVIII-XXII |
| Saint Augustine | The Happy Life; Answer to Sceptics; Divine Providence and the Problem of Evil, Soliloquies |
| Saint Augustine | The Catholic and Manichaean Ways of Life |
| Saint Augustine | Tractates on the Gospel of John 55-111 |
| Saint Augustine | Tractates on the Gospel of John 28-54 |
| Saint Augustine | Four Anti-Pelagian Writings |
| Saint Augustine | On Genesis |
| Saint Augustine | Letters, Volume 6 (1*-29*) |
| Saint Augustine | Tractates on the Gospel of John, 11-27 |
| Saint Augustine | Tractates on the Gospel of John 1-10 |
| Saint Augustine | Eighty-three Different Questions |
| Saint Augustine | Letters, Volume 3 (131-164) |
| Saint Augustine | The Teacher; The Free Choice of the Will; Grace and Free Will |
| Saint Augustine | Letters, Volume 2 (83-130) |
| Saint Augustine | The Trinity |
| Saint Augustine | Sermons on the Liturgical Seasons |
| Saint Augustine | Against Julian |
| Saint Augustine | Letters, Volume 5 (204-270) |
| Saint Augustine | Letters, Volume 4 (165-203) |
| Saint Augustine | Treatises on Marriage and Other Subjects |
| Saint Augustine | Tractates on the Gospel of John 112-124; Tractates on the First Epistle of John |
| Saint Augustine | Confessions |
| Saint Augustine | The Retractations |
