<?xml version=“1.0”?> <!DOCTYPE a [ <!ELEMENT a (#PCDATA|b|s:b)*> <!ATTLIST a xmlns:s CDATA #IMPLIED> <!ELEMENT b EMPTY> <!ATTLIST b xmlns:s CDATA #IMPLIED> <!ELEMENT s:b EMPTY> <!ATTLIST s:b xmlns:s CDATA #IMPLIED> ]> <a xmlns:s=“some.test.ns/a”>

Some text.
      <b/>
Some text.
      <s:b/>
Some text.

</a>