Codes and Ciphers, , HarperCollins Publishers, HarperCollins,Coding theory and cryptology,Research and information: general, codes;password;cryptology;ciphers;Enigma;morse code;encryption;signals;braille,, , United Kingdom, en-GBhttps://www.harpercollins.co.ukcodes;password;cryptology;ciphers;Enigma;morse code;encryption;signals;braille, [BLURB],[CITY],,books, ebooks, biblet, Book2look