<!DOCTYPE root SYSTEM "combined.dtd" >
<root xsi:noNamespaceSchemaLocation="combined.xsd"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  attBoth="lala" 
attSchema="lala" attDTD="lala"
>
<level1 >content</level1>
<level1a >content</level1a>
</root>