/usr/share/doc/libxml2-devel-2.9.1/examples/ Current File: //usr/share/doc/libxml2-devel-2.9.1/examples/test2.xml

<!DOCTYPE doc [
<!ELEMENT doc (src | dest)*>
<!ELEMENT src EMPTY>
<!ELEMENT dest EMPTY>
<!ATTLIST src ref IDREF #IMPLIED>
<!ATTLIST dest id ID #IMPLIED>
]>
<doc>
  <src ref="foo"/>
  <dest id="foo"/>
  <src ref="foo"/>
</doc>