- Alchemy--Bibliography1
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- Alessandri, Alessandro degli1
- Alessandri, Niccolò degli1
- Alessandro, Pietro di1
- Alexius, Saint1
- Alfonso V, King of Aragon, 1396-14581
- Alimony (Islamic law)1
- Allegories1
- Allegory1
- Alleluias (Chants)1
- Almagest (Ptolemy)1
- Almanach perpetuum celestium motuum (Zacuto, Abraham ben Samuel)1
- Almanacs, German1
- Almucantar1
- Alphabet--Religious aspects1
- Altoviti, Bartolomea1
- Amadori, Lorenzo1
- Ambrogio, Leonardo d'1
- Ambrose, Saint, Bishop of Milan, -3971