1. Health Level 7, Inc. http://www.hl7.org.
2. Extensible Markup Language (XML) 1.0. W3C Recommendation 10-February-1998 http://www.w3.org/TR/1998/REC-xml-19980210.html.
3. XML Schema, W3C Recommendation May 2, 2001 http://www.w3.org/XML, http://www.w3.org/2001/XMLSchema.html.
4. XSL Transformations (XSLT) Version 1.0, W3C Recommendation 16 November 1999.
5. XML Path Language (XPath) Version 1.0, W3C Recommendation 16 November 1999.