Codemaster #2
Subtitle: how to write and decode more top-secret messages
By: by Marvin Miller
Publisher: Scholastic
Published: 2005
Place of publication: New York
Language: eng
Number of pages: 70
ISBN-13: 9780439761192
Subjects: Ciphers; Cryptography
Description: This book contains fourteen new tricky codes all designed to help you keep your secrets safe.
Notes: These codes were previously published in Boy's Life magazine.

Reading level 4 ; ages 9 to 12.