1<schema xmlns="http://www.ascc.net/xml/schematron" >
2     <pattern name="a child of selected elements">
3          <rule context="CCC">
4               <assert test="parent::*[name()='BBB' or name()='DDD']">Element CCC must not be a child of element
5                    <name path="parent::*"/>
6               </assert>
7          </rule>
8     </pattern>
9</schema>
10
11