http://book.klll.cc/ebooks/subject/7600.opds 2025-08-06T10:00:54Z Books about Ciphers (sorted by popularity) Free eBooks since 1971. Project Gutenberg https://book.klll.cc webmaster@gutenberg.org https://book.klll.cc/gutenberg/favicon.ico 25 1 2025-08-06T10:00:54Z https://book.klll.cc/ebooks/subject/7600.opds?sort_order=title Sort Alphabetically by Title 2025-08-06T10:00:54Z https://book.klll.cc/ebooks/subject/7600.opds?sort_order=release_date Sort by Release Date 2025-08-06T10:00:54Z https://book.klll.cc/ebooks/26839.opds Mathematical Recreations and Essays W. W. Rouse Ball 2025-08-06T10:00:54Z https://book.klll.cc/ebooks/75074.opds Elementary cryptanalysis Helen Fouché Gaines 2025-08-06T10:00:54Z https://book.klll.cc/ebooks/48871.opds Manual for the Solution of Military Ciphers Parker Hitt 2025-08-06T10:00:54Z https://book.klll.cc/ebooks/42297.opds La Cryptographie, ou, l'art d'écrire en chiffres (French) P. L. Jacob