A Gentle Introduction to SGML
the DocBook Technical Committee of OASIS
DocBook: The Definitive Guide
SP - SGML parser by James Clark
perlSGML - SGML document manipulation package
The XML Specification
A Technical Introduction to XML
The HTML Specification
Jade - DSSSL engine by James Clark
The Modular DocBook Stylesheets by Norman Walsh
The Cascading Stylesheet Specification
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