5 books
Hints to the Decipherer of the Greatest Work of Sir Francis Bacon
Fundamental Principles of the Baconian Ciphers and Application to Books of the Sixteenth and Seventeenth Centuries (Classic Reprint)
Fundamental Principles of the Baconian Ciphers, and Application to Books of the Sixteenth and Seventeenth Centuries (Large Text Classic Reprint)
The Keys for Deciphering the Greatest Work of Sir Francis Bacon
Fundamental Principles of the Baconian Ciphers, and Application to Books of the Sixteenth and Seventeenth Centuries