dtd6 168 B

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  1. <?xml version="1.0"?>
  2. <!DOCTYPE doc [
  3. <!ELEMENT doc (a | b)*>
  4. <!ELEMENT a (#PCDATA)>
  5. <!ELEMENT b (#PCDATA)>
  6. ]>
  7. <doc><a>This</a><b> is a valid</b><a> document</a></doc>