XML source

<?xml version="1.0"?>
<xslTutorial >
<AAA id='a1' pos='start'>
     <BBB  id='b1'/>
     <BBB  id='b2'/>
</AAA>
<AAA  id='a2'>
     <BBB  id='b3'/>
     <BBB  id='b4'/>
     <CCC  id='c1'>
          <CCC  id='c2'/>
     </CCC>
     <BBB  id='b5'>
          <CCC  id='c3'/>
     </BBB>
</AAA>
</xslTutorial>