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