The metadata of the edited texts as well as the research articles are provided via the interface <ref xmlns="http://www.tei-c.org/ns/1.0" target="http://edition-humboldt.de/api/v1.1/oai-pmh.xql?verb=Identify">http://edition-humboldt.de/api/v1.1/oai-pmh.xql?verb=Identify</ref> according to the <ref xmlns="http://www.tei-c.org/ns/1.0" target="https://www.openarchives.org/pmh/">Protocoll for Metadata Harvesting of the Open Archive Initiative</ref>. Thus, these texts are also automatically referenced in the <ref xmlns="http://www.tei-c.org/ns/1.0" target="https://www.base-search.net/">Bielefeld Academic Search Enginge (BASE)</ref>. As a metadata format for OAI-PMH, only Dublin Core is currently supported.