The \x field-specific-switch an XPATH formated string to be returned. Since XPATH exist in different version it should be stated precise, which kind of XSLT is expected

Define the expected version of XPATH

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Section 2.16.5.34

Ed

Proposed Disposition of DIS 29500 Comment DK-0126 (Modified: 2007-12-17) Agreed; the following entries will be added to the Normative References clause for Part 4: XSLT, Clark, James, "XSL Transformations (XSLT) Version 1.0," World Wide Web Consortium Recommendation. 1999. http://www.w3.org/TR/xslt. XPATH, Clark, James; DeRose, Steve "XML Path Language (XPath) Version 1.0," World Wide Web Consortium Recommendation. 1999. http://www.w3.org/TR/xpath. Similar Comments: CA-0025 , CL-0120 , CO-0121 , DE-0107 , DK-0124 , DK-0125 , FR-0255 , GB-0262 , GR-0048 , KE-0028 , PT- 0062 , US-0106 , VE-0025