- Jerome, Saint, -419 or 4201
- John,--the Baptist, Saint--Poetry.1
- Kartause Marienburg (Weddern, Germany) Inscription.1
- Klosterkirche Lambach Ownership.1
- Königliche Bibliothek zu Berlin Stamp (v. 2)1
- Libri, Bartolommeo di, fl. 1482-1511.1
- Machlinia, William de, active 1481-1486, printer.1
- Mansion, Colard, active 15th century, printer1
- Manuzio, Aldo, 1449 or 1450-1515, printer1
- Manzoni, Giacomo,--1816-1889--Bookplate1
- Maritnus,--Saint, bishop of Tours,--316?-397?1
- Marshall, Harold--Bookplate1
- Marshall, J. T.--Autograph1
- Marston, Thomas E.--Bookplate.1
- Martini, Giuseppe, 1870-1944--Autograph1
- Maskell, William,--1814?-1890--Autograph1
- Maus, Edmee--Bookplate.1
- Maximilian--I,--Holy Roman Emperor,--1459-15191
- Medici, House of1
- Medici, Lorenzo de’, 1449-14921
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