By the way, Chapter 3 "Navigation" of the "XQuery: The XML query language" book by Michael Brundage is available online on Michael's site (PDF version). Take a look at http://www.qbrundage.com/xquery/toc.html.
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Yasser Shohoud's great "Real World XML Web Services" book is available online at http://www.learnxmlws.com/book.
[Via Yasser himself.]
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