3 <!ENTITY % deftest "<!ELEMENT test (#PCDATA) >">
4 <!ENTITY % defmiddle "<!ELEMENT middle (test) >">
5 <!ENTITY % defroot "<!ELEMENT root (middle) >">
6 <!ELEMENT root (middle)>
7 <!ELEMENT middle (test)>
8 <!ELEMENT test (#PCDATA)>
10 <root><middle><test>sample</test></middle></root>