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id() 関数

[16] XQuery 1.0 and XPath 2.0 Functions and Operators (Second Edition) ( (2010-12-17 00:06:54 +09:00 版)) <http://www.w3.org/TR/2010/REC-xpath-functions-20101214/#func-id>

[17] XQuery 1.0 and XPath 2.0 Functions and Operators (Second Edition) ( (2010-12-17 00:06:54 +09:00 版)) <http://www.w3.org/TR/2010/REC-xpath-functions-20101214/#func-element-with-id>