Definitions for "Document type declaration"
Keywords:  dtd, doctype, sgml, declared, markup
a line of code in a document that identifies the DTD
an SGML markup declaration which starts with the keyword DOCTYPE (or its declared replacement)
Provides technical information to SGML authoring and publishing software about how the DTD and encoded document will use SGML.
Keywords:  xpath, xslt, can't, logical, thus
a logical structure that is not accounted for in the XSLT/XPath data model, and thus you can't create it in the result result tree like you would an element