| Cengage Learning, March 30, 2015, cover price $14.95 | About this edition:
Explore Endangered Species takes readers around the world to learn about various endangered species, including polar bears, crocodiles, whooping cranes, and cheetahs.
, titled "The Mars Arena" | Gold Eagle, August 1, 1997, cover price $5.50 | also contains The Mars Arena
| About this edition:
While searching the Western badlands for the wreckage of a crashed space station, Ryan Cawdor and his team become caught in the middle of a vicious war between rival regional barons, with the life of Ryan's son hanging in the balance.