<grammar xmlns="http://relaxng.org/ns/structure/1.0" xmlns:t="http://www.thaiopensource.com/ns/annotations" xmlns:a="http://relaxng.org/ns/compatibility/annotations/1.0" datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">

   <start>

         <ref name="TEI.2"/>

   </start>

   <define name="IGNORE">

      <notAllowed/>

   </define>

   <define name="INCLUDE">

      <empty/>

   </define>

  <include href="demo3.rng"/>

   <define name="TEI.2">

      <element name="TEI.2">

         <text/>

      </element>

   </define>

</grammar>