Collections indexed by UDC

In countries in which the UDC is the main classification system (see the list), national union catalogues and national bibliographies will also contain UDC numbers. These databases are often large and are valuable information resources organized by UDC.

28 mil records

Vserossiisky Institut Nauchnoi i Tekhnicheskoi Informatsii (VINITI) - All-Russian Scientific and Technical Information Institute of Russian Academy of Sciences is the leading information centre in Russia and CIS countries. VINITI uses UDC as supplementary classification and to index selected material. However, all documents in the 28 milion large VINITI Data Bank have State Rubricator of Scientific and Technical Information codes mapped to UDC through a concordances table. VINITI Data Bank consists of:

  • multi-thematic databases (retrospective since 2001) growing annually by 700,000 records
  • 30 thematic abstract databases for Natural and Pure Sciences . Growing annualy by 1 mil records.
Slovak National Library Catalogue
4 mil records

Catalog of the Slovak National Library has 4.7 mil records (part of the collection still lacks full bibliographic description).

3.5 mil records

Slovenian national union catalogue.

3 mil records

The Network of Libraries and Information Centers in Switzerland (NEBIS) comprises of over 80 university, technical college and research institute libraries from all language regions. NEBIS is a member of the Informationsverbund Deutschschweiz IDS

3 mil records

Romanian Library Network Science & Technology Portal The Romanian national virtual catalogue based on Metalib system is a distributed catalogue which offers the possibility of simultaneous searching of bibliographic databases and other heterogeneous electronic resources. ROLiNeST was created initially for a number of university and public libraries, and is now open to new participants.

2.9 mil records

Hungarian National Union Catalogue (MOKKA) contains over 2.9 mil records indexed by UDC

2 mil records

Union Catalogue of the Czech Republic (CASLIN) contains 3,599,378 records, UDC index is present in 2,048,631 of them.

1.5 mil records

Portuguese National Bibliographic Database Currently, PORBASE is the largest bibliographic database in Portugal and reflects the collections of the National Library and over 170 portuguese libraries of different types and dimensions, both private and public

1.5 mil records

The State Public Scientific and Technical Library of Russia (Gosudarstvennaja publichnaja nauchno-tehnicheskaja biblioteka Rossii)

1.5 mil records

The Library on Natural Sciences of the Russian Academy of Sciences (Biblioteka po estestvennym naukam Rossiiskoy akademii nauk)

Czech National Bibliography
0.5 mil records

Czech National Bibliography contains 902.505 records, 554.812 of them is indexed by UDC

Croatian National and University Library Catalogue
0.5 mil records

OPAC of the Croatian National and University Library in Zagreb has 509.000 records

0.6 mil records

Hungarian National Bibliography (MNB) contain 612,352 records (books, e-documents, cartographic documents, music prints and manuscripts, and sound recordings).

600 journal titles

American Meteorological Society - Meteorological & Geoastrophysical Abstracts (MGA) contains records drawn from the World's literature on meteorology, climatology, atmospheric chemistry and physics, astrophysics, hydrology, glaciology, physical oceanography and environmental sciences. Summaries from over 600 journal titles, as well as conference proceedings, books, technical reports and other monographs, are included. Each record includes complete citation information, Universal Decimal Classification subject classifications, and subject descriptors drawn from the MGA Controlled Vocabulary. Online versions of the Controlled Vocabulary and the UDC subject classifications are available to facilitate online searching.

National bibliographies indexed by UDC


  • (430) Germany (until 2003)
  • (437.1/.2) Czech Republic
  • (437.6) Slovakia
  • (438) Poland
  • (439) Hungary
  • (460) Spain
  • (469) Portugal
  • (470+571)Russian Federation
  • (474.2) Estonia
  • (474.3) Latvia
  • (474.5) Lithuania
  • (476)Belarus
  • (477) Ukraine
  • (478) Moldova
  • (480) Finland
  • (496.5) Albania
  • (497.11) Serbia
  • (497.2) Bulgaria
  • (497.4) Slovenia
  • (497.5) Croatia
  • (497.6) Bosnia and Hercegovina
  • (497.7) Macedonia, Former Yugoslav Republic of
  • (498) Romania


  • (575.2) Kyrgyzstan


  • (611) Tunisia
  • (64) Morocco
  • (65) Algeria
  • (663) Senegal
  • (665.8) Cape Verde
  • (691) Madagascar