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- Project Gutenberg
- Bacon, Francis, 1561-1626 — Cipher
Bacon, Francis, 1561-1626 — Cipher — Audiobooks
The Mystery of Francis Bacon
by William T. (William Thomas) Smedley
Concerning the bi-literal cypher of Francis Bacon discovered in his works
by Elizabeth Wells Gallup
Ciphers For the Little Folks
by Dorothy Crain