docbook2X converts DocBook to Texinfo in two steps:
Texi-XML is simpler than DocBook and closer to the Texinfo format; it is intended to make the stylesheets' job easier.
The stylesheet for this purpose is in xslt/texi/docbook.xsl. For portability, it should always be referred to by the following URI:
          http://docbook2x.sourceforge.net/latest/xslt/texi/docbook.xsl
     
     Run this stylesheet with db2x_xsltproc.
     
db2x_texixml.
        The docbook2texi (see Wrapper scripts manual page) command does both steps automatically,
but if any problems occur, you can see the errors more clearly
if you do each step separately:
     $ db2x_xsltproc -s texi mydoc.xml -o mydoc.txml
     $ db2x_texixml mydoc.txml