16 books • 8 series
The Unknown Universe
Man?s Best Friend
The Big Questions
Big Questions: The Universe
Kosmische Reise
Die Grossen Fragen - Universum
Thinking with Demons
Tales of the Council of Elders (The Imperium Saga)
Project U.L.F. Reacquisition (Project U.L.F.)
Project U.L.F.
Journey to the Stars
The Universe (Universe)
Earth (Universe) (Universe (2nd Edition)) (Universe (Heinemann)) (Heinemann Infosearch)
Witchcraft and Magic in Europe, Volume 4: The Period of the Witch Trials
Witchcraft and Magic in Europe (History of Witchcraft and Magic in Europe, VOLUME 4)
Discovering the Universe (Young Encyclopedia) (Inside Look)