1  <?xml version='1.0'?>
2  <!DOCTYPE root [
3  <!ENTITY % deftest '&lt;!ELEMENT test (#PCDATA) >' >
4  <!ENTITY % defmiddle '&lt;!ELEMENT middle (test) >' >
5  <!ENTITY % defroot '&lt;!ELEMENT root (middle) >' >
6  %defroot;%defmiddle;%deftest;
7  ]>
8  <root><middle><test>sample</test></middle></root>