G Edward Barton,Robert C Berwick,Eric Sven Ristad <br/><br/>
Computational Complexity and Natural Language 

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 -  MIT Press  1987 
 - 335 
<br/><br/>  
<br/><br/><label>ISBN: </label>0-262-02266-4 
<br/><br/><label>Dewey Class. No.: </label>004.8