Sinkov, Abraham <br/><br/>
Elementary cryptanalysis a mathematical approach 

 - Washington D.C.  The mathematical association of America  1966 
 - ix,222p.  23 cm. 
 - New Mathematical library .
<br/><br/><label>ISBN: </label>0883856220 
<br/><br/><label>Dewey Class. No.: </label>005.82,D,sin  / _