1<!ENTITY % b SYSTEM "http://example.org/b/b.dtd">
2%b;
3<!ENTITY % c SYSTEM "http://example.org/c/c.dtd">
4%c;
5<!ENTITY % a SYSTEM "http://example.org/a/a.dtd">
6%a;
7<!ELEMENT bca (b, c, a)>
8