Does DTD allow deriving all possible paths in an XML document?

[ycao5@scs.carleton.ca]

Hello everyone,

     I have one question about XML DTD. In a paper, the authors say  
that DTD allows deriving all possible paths from the root to the  
leaves appearing in related XML documents. Does this statement  
correct? Based on my knowledge, DTD may not contain all possible  
elements in an XML document. I would like to get your opinion. Thanks.