"kryptering" . . "koder" . . . . "Jenna LaReau" . . "Top secret : a handbook of codes, ciphers and secret writing" . . . "Top secret : a handbook of codes, ciphers, and secret writing" . "Top secret : a handbook of codes, ciphers, and secret writing"@en . . . . . "Juvenile works" . "Juvenile works"@en . . "Top secret a handbook of codes, ciphers, and secret writing"@en . . . . . "Learn how to make and break codes, master cipher systems, and experiment with secret writing."@en . . "A handbook for the budding cryptographer including codes and ciphers, invisible inks, concealment techniques, spy stories and some history." . "A handbook for the budding cryptographer including codes and ciphers, invisible inks, concealment techniques, spy stories and some history."@en . "Top Secret : A Handbook of Codes, Ciphers, and Secret Writing"@en . . "Top secret" . . "Presents a guide to codemaking, codebreaking, and their role in history, describing different types of codes and ciphers, discussing codebreaking and concealment techniques, and including brief stories about exciting moments in the history of the art."@en . . . . . . . . . . . . . . . . . . "Cryptography- Juvenile Nonfiction Ciphers- Juvenile Nonfiction Codes- Juvenile Nonfiction." . . "hemmelige koder" . . "Codes secrets." . . "kodebrydning" . .