CHeriCoS

Open Library recently announced the availability of a RESTful API to access Open Library book metadata in RDF/XML format, which combines elements of the Dublin Core metadata terms with some elements from bibliontology and the registered RDA schemas. This service is in an early stage. The given example returns a nice RDF/XML, but without namespace declarations, whereas this book of Edgar Allan Poe returns a RDF/XML with declarations. Open Library offers several identifiers for their entries like Dewey, LC, ISBN 10, ISBN 13, LCCN, IA & OCLC, so this service could be very helpful when making mashups of data from museums, archives and libraries.