2001 - Codes and Ciphers Julius Caesar the Enigma and the Internet (Paperback) → Hardcover ISBN-13: 9780521008907 ISBN-10: 0521008905 Genres: Business & Money, Computers & Technology, Science & Math ? 2001 - Codes and Ciphers Julius Caesar the Enigma and the Internet (Hardcover) → Paperback ISBN-13: 9780521810548 ISBN-10: 052181054X Genres: Business & Money, Computers & Technology, Science & Math ? |