CENL (Foundation Conference of European National Librarians)
https://www.cenl.org/
LIBER (Ligue des Bibliothèques Européennes de Recherche – Association of European Research Libraries)
https://libereurope.eu/
ISBN (International Standard Book Number)
https://www.isbn-international.org/
ISSN (International Standard Serial Number)
https://www.issn.org/
ISMN (International Standard Music Number)
https://ismn-international.org/
