Former Owner
- Constance de Foix1
- Convent San Marco1
- Convento di San Giusto alle Mura1
- Convento di San Paolo1
- Cordwainer Smith1
- Cornelius John Hauck1
- Corp. Thomas Tay1
- Cortlandt F. Bishop2
- Cosimo de' Medici1
- Count Alexis de Golowkin1
- Count Johann Nepomuk Wilczek1
- Couvent des Minimes (Clermont-Tonnerre, France)1
- Cover of a binding, illegible on what was the outer side.1
- Craven Ord1
- Cristoferus Chrewczer1
- Curt H. Reisinger1
- Cyrus Longworth Lundell1
- D. Andreas Parisino1
- D. D. Horatius Bosner1
- D. Manning1