Kahn, David,  1930- <br/><br/>
Seizing the enigma :  the race to break the German U-boat codes, 1939-1943 / 
David Kahn. 
 - Boston :  Houghton Mifflin Co.,  1991. 
 - xii, 336 p., [16] p. of plates :  ill., maps ;  24 cm. 
<br/><br/> "A Thomas Congdon book"--T.p. verso. 
<br/><br/>Includes bibliographical references (p. [311]-326) and index. 
<br/><br/><label>ISBN: </label>0395427398 :  $24.95 
<br/><br/><label>LCCN: </label>90025128  
<br/><br/><label>Subjects--Topical Terms: </label><br/>World War, 1939-1945--Cryptography.<br/>World War, 1939-1945--Naval operations, German.<br/>World War, 1939-1945--Naval operations--Submarine.
<br/><br/><label>Subjects--Index Terms: </label>World War, 1939-1945 -- Naval operations -- Submarine 
<br/><br/><label>LC Class. No.: </label>D810.C88  / K34 1991 
<br/><br/><label>Dewey Class. No.: </label>940.54/85