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Ciphers
5 books
Mathematical Recreations and Essays
W. W. Rouse (Walter William Rouse) Ball
Ciphers for the little folks
Dorothy Crain, Helen Louise Ricketts
La Cryptographie, ou, l'art d'écrire en chiffres
P. L. Jacob
Manual for the Solution of Military Ciphers
Parker Hitt
Elementary cryptanalysis
Helen Fouché Gaines, George C. (George Chester) Lamb