Maihingen - Münster
- Maihingen (see Augsburg UB)
Öttingen-Wallerstein Library (now dissolved)
- Magdeburg
City Library
- Mainz
Martinus Library
City Library
Cathedral and Diocesan Archives, Gutenberg Museum, City Archives, University Library as a deposit in the Scientific City Library (see Specials: Datenbanken, Handschriftencensus RLP)
- Marburg
State Archives
University Library
- Maria Laach (see Specials: Databases, Manuscript Census RLP)
Library of the Abbey
- Memmingen
City Archive
- Mengeringhausen
City and church archives
- Merseburg
Cathedral Library
- Metelen (see Specials: Manuscript Census Westphalia)
St. Cornelius and Cyprian
- Michelstadt
Nicolaus Matz Library
- Milte (see Specials: Handschriftencensus Westfalen)
St. Johannes
- Minden (see Specials: Manuscript Census Westphalia)
Cathedral St. Peter and Gorgonius
- Mönchengladbach (see Specials: Manuscript Census Rhineland, vol. 2)
Library "Science and Wisdom" of the Cologne Franciscan Province
Cathedral Archives (Cath. Parish of the Assumption of Mary)
- Mühlhausen (see Specials: Eastern Germany)
City Archive
- Mühlheim a.d. Ruhr (see Specials: Handschriftencensus Rheinland, vol. 2)
City Archiv
- Munich
State Library
University Library
Royal Bavarian National Museum (histor. collection)
- Münster
University and State Library
(see Specials: Manuscript Census Westphalia) Bible Museum, Diocesan Archives (Cathedral Archives and others), Diocesan Library, Historical Seminar of the Westphalian Wilhelm University,Capuchins, North Rhine-Westphalian State Archives, St. Lamberti, St. Mauritz, City Archives, City Museum, Study and Central Library of the Franciscans, Westphalian State Museum of Art and Cultural History
