The electronic publishing process implies in generell certain attributes: "fast, cost-saving, worldwide acessible". Seen from the author's or the user's perspective, however, those attributes are sufficient to ensure permanent access to the electronic publication? The usual experience with the Internet promises not a sufficient result: URLs don't offer a mechanism that allows internet based publications to be identified unequivocally and being traceable at anytime. One solution to that situation is being provided by Persistent Identifiers such as Uniform Resource Names (URN), whose implementation Die Deutsche Bibliothek consolidates within the scope of the project EPICUR.
An implementation in local contexts cannot provide the persistency of that addressing scheme on its own. For example, if an institution ceases the maintenance and provision of a digital collection, their references – even when applied by a persistent adressing scheme – would equally be volatile as in case of URLs. To ensure a long-term usability of a permanent addressing scheme such as URN, it is necessary tocreate an infrastructure with an institutional backup.
The talk focusses on a general description of the Persistent Identifier activities worldwide and on productive implementations. Based on the EPICUR project in Die Deutsche Bibliothek, a prospect on continuative activities will be given.