Introduction to automata theory, languages and computation 
Hopcroft, John E. 
 -  Addison-Wesley Publishing Company.  2001 
 - 521 pages. 
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<br/><br/><label>ISBN: </label>0-321-21029-8 
<br/><br/><label>Dewey Class. No.: </label>511.35 H77i 2003