13.6.2 DTDHandler Objects 
DTDHandler instances provide the following methods:
- notationDecl (name, publicId, systemId)
 - 
  Handle a notation declaration event.
 
- unparsedEntityDecl (name, publicId,
                                                   systemId, ndata)
 - 
  Handle an unparsed entity declaration event.
 
See About this document... for information on suggesting changes.