In the Special Collection Reference Library: Text at entrance 4 of the second floor (go right) you can find:

• journals, reference works, bibliographies;
• manuscript catalogues classified by language or people (Z6605), by subject (Z6611), by region or country (Z6620) and by library (Z6621);
• literature on codicology and palaeography (Z105-115.5) and on manuscript illumination (ND2289-2416).

The volumes are shelved according to the Library of Congress Classification. The LCC-shelfmarks in the online catalogue and on the spine labels of the volumes differ from those of the Study Area (first floor), in that they begin with “II-4”. For a survey of the reference library’s content see the subject guide Manuscripts, archives and letters: further information.

In the Special Collections Reading Room (second floor, entrance 4, go left) you can use: palaeographical atlases (DOUSA 86) and printed facsimile’s of medieval manuscripts kept outside Leiden, shelved according to content, cultural region (DOUSA 87) and illumination (DOUSA 88). For an overview see the subject guide Manuscripts, archives and letters: further information.

In Room 211 (second floor, entrance 5, go right) you can find a card file accessing micro forms of about 1700 handschriften kept in other institutions. There is an alphabetic index on location and shelfmark. After requesting the micro forms in the Special Collections Reading Room use one of the readers in Room 211 to consult them.

• CERL’ List of Web Resources for Manuscripts and archives — Links with comments, divided into four sections: Institutional collections – Beyond institutional collections – Research tools – Educational and other resources
• CERL Manuscripts Expert Group (Europe) — the National Backgrounds inform per country about the major manuscripts and archives collections and the holding institutions
• Amsterdam, Bibliotheek Universiteit van Amsterdam — special collections
• Den Haag, Koninklijk Bibliotheek — special collections
• Den Haag, Letterkundig Museum — manuscripts and letters from Dutch literary authors and publishing houses (Dutch)
• Groningen, Universiteitsbibliotheek — special collections
• Utrecht, Universiteitsbibliotheek — special collections
• BnF Archives et manuscrits — manuscripts and archives in the Bibliothèque nationale de France
• Catalogue Collectif de France — manuscipts and archives in other French libraries; includes repertory with information about 5000 libraries (see also À propos CCfr)
• British Library — manuscripts and archives

In Room 211 (second floor, entrance 5, go right) you can use the Bibliotheca Neerlandica Manuscripta: documentation on Middle Dutch manuscripts kept world wide.

BNM collects and makes available information about Middle Dutch texts and their authors, about the persons involved in the production of the manuscripts containing those texts, and about the owners from the Middle Ages up to the present. The documentation comprises The textual and codicological data

The manuscript descriptions — kept in folders and boxes that are placed in two bookcases (approximately 8 metres) — are arranged by location and shelfmark. The textual, codicological and book-historical data of these descriptions have been noted down on cards and arranged in several card indexes. There are three important files: authors and textual headwords; scribes and owners; scriptoriums and libraries.

The BNM can also be consulted via the internet. All manuscript description have been digitized; the inventory in the collection guide Bibliotheca Neerlandica Manuscripta contains links to the scans in Digital Special Collections.

Since 1991 two-thirds of the card files, checked and supplemented with information from recent publications, have been converted into electronic data and incorporated in a databasethe. In 2017, thanks to a grant from CLARIN, this database came available in a version developed by Huygens ING, in collaboration with Leiden University and Utrecht University: Bibliotheca Neerlandica Manuscripta & Impressa (BNM-I).

• Medieval Manuscripts in Dutch Collections — manuscripts in Latin script kept in Dutch institutions (including Leiden)
• Medieval Illuminated Manuscripts — kept in the Koninklijke Bibliotheek & Museum Meermanno, The Hague
• Luxury Bound — over 3800 handschriften illuminated with miniatures or historiated initials  in the Nederlands between 1400 and 1550
• Bibliotheca Neerlandica Manuscripta (database) — Middle Dutch manuscripts kept world wide (including Leiden)
• Schoenberg Database of Manuscripts — data on more than 125.000 medieval manuscript books (no fragments) produced before 1600
• Koninklijke Bibliotheek Brussel — largest collection of medieval manuscripts in the Netherlands
• Manuscripta Mediaevalia — manuscripts in German-speaking countries
• e-codices — over 1500 digitized manuscripts kept in Swiss libraries
• Digital Scriptorium — medieval and early modern manuscripts kept in United States libraries
• Kristeller: Latin manuscript books before 1600 — survey of (catalogues of) manuscript collections kept world wide
• Digitized Medieval Manuscripts — overview of manuscripts digitized world wide, compiled by Giulio Menna and Marjolein de Vos
• Institut d’Histoire et de Recherches des textes  — IRHT “se consacre à la recherche fondamentale sur les manuscrits médiévaux et les imprimés anciens. L’histoire des textes écrits dans les principales langues de culture du pourtour méditerranéen, latin, langues romanes, hébreu, grec, copte, syriaque, arabe, y est traitée dans tous ses aspects: supports matériels de l’écrit, écriture et décoration, contenu textuel, iconographie, diffusion et réception”.
• Ligatus — Language of Bindings — thesaurus of bookbinding terms for book structures dating from the ninth to the nineteenth century

In Room 211 (second floor, entrance 5, go right) you can use a card catalogue for alba amicorum created in the Nederlands until 1800. With alphabetical indices of personal names (incribers and album holders).

• Archieven.nl — overview of archives and inventories; the interface searches all persons, newspapers, image databases, archive creators, and the heritage guide (archival institutions, historical societies and museums)
• Nationaal archief — holds the documents of the national government, archives of the province of Zuid-Holland and private archives
• Alba amicorum in Nederland — describes all known alba amicorum created in the Netherlands before 1800.
• Archives Portal Europe — archives and inventories from European archival institutions
• Agrippa — Flemish manuscripts and letters held by the Letterenhuis, Antwerp
• Kalliope Verbundkatalog — accesses private papers, autographs and publishers archives in over 450 German institutions
• Zentrale Datenbank Nachlässe — mainly in German archival institutions
• Archives Hub — descriptions of thousands of archive collections from nearly 300 institutions across the United Kingdom
• Wetten en regelgeving — applies to government archives (via Nationaal Archief)

In kamer 211 (second floor, entrance 5, go right) you can find the ‘Molhuysen files’. This card catalogue accesses published letters from and to Dutch scholars, compiled by P.C. Molhuysen in the years 1902-1911. The catalogue was commissioned by the Society of Dutch Literature (Committee of History and Archaeology) and is kept under shelfmark LTK 1643.

• Catalogus Epistularum Neerlandicarum (CEN) — catalogue of letters kept in Dutch institutions (limited access)
• ePistolarium — searches and analyses 20.000 letters of seventeenth-century Dutch scholars
• Agrippa — Flemish manuscripts and letters held by the Letterenhuis, Antwerp
• Agrippa — Catalogue of the Letterenhuis, Antwerp
• Kalliope Verbundkatalog — accesses private papers, autographs and publishers archives in over 450 German institutions
• Early Modern Letters Online — cataloguing project of the University of Oxford for letters from the Early modern period