xsltproc
--------
-The XSL processor xsltproc.
-(available as a package for Linux / Cygwin)
+The XSL processor xsltproc. Part of libxslt:
+http://xmlsoft.org/xslt/
+Available as a package for Linux / Cygwin.
+Supplied with Mac OS X Panther and later.
xmllint
-------
Needed to validate if the .xml files conform to the Docbook/XML DTD.
-(available as a package for Linux / Cygwin)
+Part of libxml2:
+http://xmlsoft.org/
+Available as a package for Linux / Cygwin.
+Supplied with Mac OS X Panther and later.
FOP processor (for PDF generation only)
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