167 pages • 1982 • 5 editions

fiction science fiction adventurous challenging fast-paced

183 pages • 1988 • 3 editions

fiction science fiction adventurous challenging medium-paced

262 pages • 1997 • 4 editions

fiction science fiction adventurous challenging reflective medium-paced

313 pages • 2000 • 4 editions

fiction science fiction adventurous challenging slow-paced