alt Hacker NewsTitle: Can You Crack the Code?: A Fascinating History of Ciphers and Cryptography
ISBN-10 : 1681195143 ISBN-13 : 978-1681195148
Title: Top Secret: A Handbook of Codes, Ciphers and Secret Writing
ISBN-10 : 0763629723 ISBN-13 : 978-0763629724
Thanks for the recommendations, Top Secret was just recommended elsewhere so we'll check them out.