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SHLOMIF / XML-LibXML-2.0110 / example / article_internal.xml 
<!DOCTYPE article [
<!ELEMENT article (pubData*, pubArticleID*, pubDate+, pubName+, section+, memo*, headline1*, headline2*, byline*, lead*, rest*, graphics*, keywords*, caption*)>
<!ELEMENT pubData (#PCDATA)>
<!ELEMENT pubArticleID (#PCDATA)>
<!ELEMENT pubDate (#PCDATA)>
<!ELEMENT pubName (#PCDATA)>
<!ELEMENT section (#PCDATA)>
<!ELEMENT memo (#PCDATA)>
<!ELEMENT headline1 (#PCDATA)>
<!ELEMENT headline2 (#PCDATA)>
<!ELEMENT byline (#PCDATA)>
<!ELEMENT lead (#PCDATA)>
<!ELEMENT rest (#PCDATA)>
<!ELEMENT graphics (#PCDATA)>
<!ELEMENT keywords (#PCDATA)>
<!ELEMENT caption (#PCDATA)>
]>
<article>
<pubData>Something here</pubData>
<pubArticleID>12345</pubArticleID>
<pubDate>2001-04-01</pubDate>
<pubName>XML.com</pubName>
<section>Foo</section>
<lead>Here's some leading text</lead>
<rest>And here is the rest...</rest>
</article>