1 <?xml version="1.0"?>

     2 <A xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

     3    <A xsi:type="idType" idAttr="ONE"/>

     4    <A xsi:type="idType" idAttr="ONE"/>

     5    <A xsi:type="idrefType" idrefAttr="TWO"/>

     6 </A>