Issues and examples for the XQuery Wikibook
https://en.wikibooks.org/wiki/XQuery
see also https://en.wikibooks.org/wiki/Talk:XQuery
http://www.exist-db.org/exist/apps/demo/index.html eXistdb demo examples
http://kitwallace.co.uk/Book/ evaluation of alternative approaches to common tasks
https://github.com/CliffordAnderson/XQuery4Humanists Clifford andersons XQuery for Humanists
https://github.com/joewiz/learn-xquery Joes list of Learning resources