Periodicals metadata available under CC0 1.0
The majority of the metadata in the German Union Catalogue of Serials (ZDB) have been available under “Creative Commons Zero (CC0 1.0)” conditions since June 2014. This means that roughly 1.7 million bibliographic data in all languages and with no time restrictions have been approved for further use along with more than 13 million library ownership data. The approval explicitly includes commercial use.