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[Edit Description]
Intended for Wikipedia editors who want to cite a book with a Google Books URL. Highlight such a link and click. If no text is selected, the current page's URL is taken instead, which only makes sense if you're at Google Books, of course. For more information contact Apoc2400 at http://en.wikipedia.org/wiki/User_talk:Apoc2400
Source (paradoctor.webs.com)
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Reftag Wikipedia Google Books citation template
It's like magic.