http://www.aib.it/progetti/opac-italiani/

• Biblioteca Nazionale Centrale
  • http://opac.sbn.it/opacsbn/opac/iccu/free.jsp
• Biblioteca Nazionale Centrale – Firenze
  • http://www.bncf.firenze.sbn.it/
• Biblioteca Apostolica Vaticana
  • https://www.vatlib.it/

Catalogs of the URBS network libraries

• Bibliotèque Nationale de France
  • http://www.bnf.fr/fr/acc/x.accueil.html
• Brithish Library
  • http://www.bl.uk/
• Library of Congress
  • https://catalog.loc.gov/
• The New York Public Library
  • https://www.nypl.org/
• Deutsche National Bibliotek
  • http://www.dnb.de/DE/Home/home_node.html
• Biblioteca Nacional de Espana
  • http://www.bne.es/es/Inicio/index.html