"social networking services that really work are the ones that are built around objects. (...) Flickr, for example, has turned photos into objects of sociality. On del.icio.us the objects are the URLs. EVDB, Upcoming.org, and evnt focus on events as objec
xISBN is a library web service that supplies International Standard Book Numbers (ISBNs) associated with individual intellectual works represented in the OCLC WorldCat database. Give it an ISBN, and it returns a list of associated ISBNs.
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