- Archival materials3
- Archives90
- Arcibucci, Alessandro1
- Ardabīlī, Aḥmad ibn Muḥammad, -1585. Majmaʻ al-fāʼidah wa-al-burhān fī sharḥ Irshād al-adhhān1
- Ardabīlī, Muḥammad ibn ʻAbd al-Ghanī, -1249 or 1250. Sharḥ al-Unmūdhaj1
- Ardabīlī, Muḥammad ibn ʻAbd al-Ghanī, 1572-1627. Sharḥ al-Unmūdhaj6
- Ardinghelli, Rinaldo degli1
- Argonauts (Greek mythology)1
- Arianism3
- Aringhello, Tommaso di1
- Aristotle27
- Aristotle. Nicomachean ethics1
- Aristotle. Theologia1
- Arithmetic44
- Arithmetic--Study and teaching1
- Arjuna (Hindu mythological character)33
- Arjuna (Hindu mythological character)--Early works to 18003
- Arma Christi1
- Armada (1588)6
- Armaiolo, Francesco2