The SGML/XML Web Page
A reference work for XML and its parent, SGML. Features documentation on the application of the open, interoperable "markup language" standards, including XSL, XSLT, XPath, XQuery, XLink, XPointer, XHTML, HyTime, DSSSL, CSS, SPDL, SVG, CGM, ISO-HTML, and others. (Robin Cover / OASIS)