Voyagers (Ben Bova Series Book 1)
The Return: Book IV of Voyagers (The Grand Tour 20)
Voyagers III: Star Brothers
Voyagers III (Ben Bova Series Book 3)
The Exiles Trilogy
New Earth (The Grand Tour Book 21)
Apes and Angels (Star Quest Trilogy)
Death Wave (Star Quest Trilogy)
The Star Conquerors
Powersat (The Grand Tour Book 1)