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