If you want to work with Linked Open Data you are in need of URIs. But, where are these URIs? lobid provides an alpha CQL-search interface over all the more than 18 M resources of the hbz union catalogue to help you find the proper URI.
Also, you can use the search interface as a restful API.
It is planned to provide a result set in RDFa or RDF via content negotiation to play neatly with our LOD efforts.