This presentation: http://www.cafeconleche.org/slides/xmlsig/xquery
XQuery: A Query Language for XML: http://www.w3.org/TR/xquery/
XML Query Requirements: http://www.w3.org/TR/xmlquery-req
XML Query Use Cases: http://www.w3.org/TR/xmlquery-use-cases
XML Query Data Model: http://www.w3.org/TR/query-datamodel/
The XML Query Algebra: http://www.w3.org/TR/query-algebra/
XML Syntax for XQuery 1.0 (XQueryX): http://www.w3.org/TR/xqueryx
XQuery 1.0 and XPath 2.0 Functions and Operators Version 1.0: http://www.w3.org/TR/xquery-operators/
XPath 2.0 Working Draft: http://www.w3.org/TR/xslt20
XPath 2.0 Requirements: http://www.w3.org/TR/2001/WD-xpath20req-20010214
XSLT 2.0 Working Draft: http://www.w3.org/TR/xslt20
XSLT 2.0 Requirements: http://www.w3.org/TR/2001/WD-xslt20req-20010214