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Extensible Markup Language (XML)
XML Technology
The Extensible Stylesheet Language Family (XSL)
W3C XML Query (XQuery)
Efficient Extensible Interchange Working Group
XML: Extensible Markup Language | MDN
XPath | MDN
XSLT: Extensible Stylesheet Language Transformations | MDN
RELAX NG home page
schematron.com
schxslt/schxslt
