1 <?xml version="1.0"?>

     2 <C attr="typeY"

     3    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

     4    xsi:type="Y">

     5    <C attr="typeY" xsi:type="Y"/>

     6    <A attr="typeY" xsi:type="Y"/>

     7 </C>