The XML 1.1 Bible
Elliotte Rusty Harold
Wiley, 2004
ISBN: 0-7645-4986-3
Chapter 15, XSLT: http://www.cafeconleche.org/books/bible3/chapters/15.html
XML in a Nutshell, 2nd Edition
Elliotte Rusty Harold and W. Scott Means
O'Reilly & Associates, 2002
ISBN 0-596-00292-0
Chapter 9 XPath: http://www.oreilly.com/catalog/xmlnut/chapter/ch09.html
This presentation: http://www.cafeconleche.org/slides/sd2004west/xslt/
XSL Transformations 1.0 Specification: http://www.w3.org/TR/xslt/
XPath Specification: http://www.w3.org/TR/xpath