Excerpts
Title: Secretos de la esteganografía (Secrets of Steganography)
Series: Criptología (Cryptology) (Alternator Books ® en español)
Title: Secretos de los locutores de claves navajos (Secrets of Navajo Code Talkers)
Series: Criptología (Cryptology) (Alternator Books ® en español)
Title: Sedimentary Rocks: Hit the Road and Discover a World That Rocks!
Series: The Rock Cycle Road Trip