· Content Syndication with RSS  (O'Reilly)

· Learning XML  (O'Reilly)

· XML Schema  (O'Reilly)

· XSLT  (O'Reilly)

· XML in a Nutshell  (O'Reilly)

· Java & XML, 2nd Edition  (O'Reilly)

· Java and XSLT  (O'Reilly)

· Professional XML 2nd Edition  (wrox)

· Java XML Programmer's Reference  (wrox)

· XSLT Programmer's Reference 2nd Edition  (wrox)

· Professional XML Web Services  (wrox)

· www.w3.org/XML  (Extensible Markup Language (XML) Specification)

· http://www.w3.org/RDF/  (W3C RDF Project Page)

· http://www.xml.com/pub/a/2002/12/18/dive-into-xml.html  ("What is RSS?")

· http://backend.userland.com/rss091  (RSS 0.91 Specification)

· http://purl.org/rss/1.0/spec  (RSS 1.0 Specification)

· http://backend.userland.com/rss  (RSS 2.0 Specification)

· oasis-open.org  (Non-profit XML standards consortium)

· xml.com

· xml.org  (XML industry portal)

· xmlhack  (XML developer news)

· xml.oreilly.com  (O'Reilly XML Network)

· XML101.com

· relaxng.org  (RELAX NG schema language)

· Sun Multi-Schema XML Validator  (A Multi-Schema XML Validator supporting RELAX NG, RELAX Namespace, RELAX Core, TREX, XML DTDs, and a subset of XML Schema Part 1)

· libxml and libxsl  (The Gnome XML and XSLT toolkit)

· expat  (XML parser library written in C)

· Tidy  (HTML, XHTML, and XML syntax checking and formatting)

· Apache XML project  (Home of the Xerces XML parser, and the Xalan XSLT processor)

· IBM Alphaworks - XML  (Parsers, Validators, Editors, etc...)

· Ginger Alliance  (Sablotron XSLT parser)