<?xml version="1.0"?>
<!DOCTYPE mydtd [
 <!ENTITY e "&#38;">
 <!ENTITY a "abc">
 <!ENTITY b "<foo></foo>">
 <!ENTITY % c "'foo'">
 <!ENTITY f SYSTEM "t3.xml">
  ] >
<a b="&a;">
  &b;
  &e;b;>
  &f;
  &amp;
</a>
