Jade
   An early implementation of an XSL processor. Converts XSL to DSSSL to render XML.
   http://www.cogsci.ed.ac.uk/~ht/xslj.html

Jeni's XSLT Pages
   Jeni Tennison is a very active XSLT community member. This page is her homepage for her many XSLT activities. With 25 tutorials/articles and 2 utilities for visitors. Good website.
   http://www.jenitennison.com/xslt/index.html

MSDN's XSLT Developer's Guide
   The successor to Extensible Stylesheet Language (XSL), XSL Transformations (XSLT) is an XML-based language that enables you to transform one class of XML document to another
   http://msdn.microsoft.com/library/default.asp?url=/library/en-us/xmlsdk30/htm/xmconxsldevelopersguide.asp

TopXML XSLT Zone
   With 34 original articles, the XSLT Zone explains XSLT in various solutions - such as .NET, mobile solutions and in applications. These articles range from introductory to advanced; through to tutorials and include complete XSLT and XPath references.
   http://www.topxml.com/xsl

UWOBO XSL Processor
   Invoked via URL giving the URI of an XML document and a list of stylesheets to be applied. Requires Tomcat and Xerces/Xalan.
   http://helm.cs.unibo.it/uwobo/

XML Cover Pages: Extensible Stylesheet Language (XSL)
   Introduction, history, articles and software support by Robin Cover. (Oasis)
   http://www.oasis-open.org/cover/xsl.html

XSL Lint
   A semantic lint checker for that detects poor syntax and redundant areas of a stylesheet.
   http://nwalsh.com/obsolete/xslint/

XSL Transformations (XSLT) Version 1.0
   This specification defines the syntax and semantics of XSLT, which is a language for transforming XML documents into other XML documents. (W3C Recommendation 16 November 1999)
   http://www.w3.org/TR/xslt

XSLT Requirements Version 2.0
   This draft document describes the requirements for the XSLT 2.0 specification. (W3C Working Draft 14 February 2001)
   http://www.w3.org/TR/xslt20req