Author
- Aldobrandino da Siena1
- Alexander III1
- Alexander IV1
- Alexander VI1
- Alfonso X of Castile and Leon1
- Alfonso de Cartagena1
- Andrea Goussen1
- Andrea Gritti1
- Angelus Callimachus de Monteviridi1
- Anquetil Raolée1
- Anselm of Canterbury1
- Anthonius Charrcon1
- Antoine Vincent1
- Antonio dalle Conchelle1
- Arles1
- Armenian Catholic Church1
- Arnaldus de Villa Nova1
- Arnulf of Bohéries1
- Athanasius of Alexandria1
- Augustinus Triumphus1