Incoming Resources
- Secret messages, concealment, codes, and other types of ingenious communication, William S. Butler and L. Douglas Keeney
- Code cracking for kids, secret communications throughout history, with 21 codes and ciphers, Jean Daigneau
- Pass it on!, all about notes, from secret codes and special inks to fancy folds and dead man's drops, by Sharon Bailly ; illustrations by Anne Canevari Green
- Latest intelligence, an international directory of codes used by government, law enforcement, military, and surveillance agencies, James E. Tunnell ; edited by Helen L. Sanders
- Top secret, a handbook of codes, ciphers, and secret writing, Paul B. Janeczko ; illustrated by Jenna LaReau
- The manga guide to cryptography, Masaaki Mitani, Shinichi Sato, Idero Hinoki, and Verte Corp
- Codes and ciphers, Adrian Gilbert
- Destroy after reading, the world of secret codes, Mary Colson
- Codes and sequences, by Marion Smoothey ; illustrated by Ann Baum
- Codes and codebreaking, Andrew Langley
- Codes, ciphers & other cryptic & clandestine communication, making and breaking secret messages from hieroglyphs to the Internet, by Fred B. Wrixon
- Messages in code, Janet Weller ; illustrated by Colin Mier
- Classic codes and ciphers, Rachael L. Thomas
- Creating and cracking codes, Lesley McFadzean
- Break the code, cryptography for beginners, Bud Johnson ; illustrations by Larry Daste
- Breaking the code with cryptography, analyzing patterns, Janey Levy
- Secrets of steganography, Rachael L. Thomas
- The kids' code and cipher book, Nancy Garden
- The cat's elbow and other secret languages, collected by Alvin Schwartz ; pictures by Margot Zemach
- Codes, ciphers, and other secrets, Karin N. Mango
- The code book, how to make it, break it, hack it, crack it, Simon Singh
- The secret code book, Helen Huckle
- Mysterious messages, a history of codes and ciphers, Gary Blackwood ; designed and illustrated by Jason Henry
- Codes, ciphers, and cartography, math goes to war, Terry Burrows
- Making secret codes and messages, by Deanna Caswell
- Spy codes and ciphers, by Susan K. Mitchell
- Codes and ciphers, Fred B. Wrixon
- Create your own secret language, invent codes, ciphers, hidden messages, and more : a beginner's guide, David J. Peterson ; illustrations by Ryan Goldsberry
- Create your own secret language, invent codes, ciphers, hidden messages, and more : a beginner's guide, David J. Peterson ; illustrations by Ryan Goldsberry
- Making secret codes, by Jillian Gregory ; Consultant Professor Mihir Bellare
- Can you crack the code?, a fascinating history of ciphers and cryptography, Ella Schwartz ; illustrated by Lily Williams
- The codebreakers, the story of secret writing, David Kahn
- Codes, ciphers, and secret languages, Fred B. Wrixon
- Top secret!, codes to crack, Burton Albert, Jr. ; illustrated by Jerry Warshaw
- Professional cryptologists, Rachael L. Thomas
- Ciphers and codes, Karen Price Hossell