Former Owner
- Melk Abbey2
- Menno Hertzberger1
- Mercantile Library Company1
- Merlemont family1
- Meschatin La Faye family1
- Messieurs Du Trieu2
- Michael Kantakouzenos Şeytanoğlu1
- Michael Krupp1
- Michael M. Zagayski1
- Michael Tomkinson2
- Michael Wodhull1
- Michaeliskonvent1
- Michel Chasles1
- Michel Ferdinand d'Albert d'Ailly1
- Michel de Léon1
- Michele Amari1
- Michele Cavaleri2
- Michiel family1
- Middle Hill Rare Books & Manuscripts AB (Stockholm, Sweden)1
- Mikhail Golitsyn2