dtd8 197 B

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  1. <!DOCTYPE doc [
  2. <!ELEMENT doc ((a | b) , (c | d))+>
  3. <!ELEMENT a (#PCDATA)>
  4. <!ELEMENT b (#PCDATA)>
  5. <!ELEMENT c (#PCDATA)>
  6. <!ELEMENT d (#PCDATA)>
  7. ]>
  8. <doc><b>This</b><c> is a valid document</c></doc>