Possible Clues:

• Gods, to Livy
• 'Agnus ' (Mass prayer)
• ''Agnus __'' (Mass prayer)
• Mater ___ (the Virgin Mary)
• Agnus (lamb figure) --
• See 49-Down
• ''Agnus __'' (mass movement)
• Opus ___ ('The Da Vinci Code' organization)
• 'Fabien ___ Franchi' (Oscar Wilde poem)
• "De Civitate __": "The City of God," St. Augustine work