Library of Congress	Catalogo della Library of Congress (USA)
	British Library	Catalogo della British Library (UK)
	Bibliothéque nationale de France BNF - Catalogue général
	Karlsruhe Virtueller Katalog
	WorldCat - OCLC FirstSearch
	The European Library
	Incunabula Short Title Catalogue	ISTC - Incunabula Short Title Catalogue
	USTC Universal Short Title Catalogue	USTC Universal Short Title Catalogue
	MEI - Material Evidence in Incunabula
	Il Portale del CERL - manoscritti e materiale a stampa antico