A number of very good additional resources are available on the Web for learning about XML. Here is one of the best to consult:
XML 1.0 Recommendation (http://www.w3.org/TR/REC-xml) The XML 1.0 Recommendation (Second Edition) from the W3C is the final word on XML. If you have a question about a technical aspect of XML, this should be the first source you consult.
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