The Hitchhiker's Guide to the Galaxy is a 9-book series with 6 primary works first released in 1979 with contributions by Douglas Adams, Jem Roberts, and 4 others.
2002 • 100 Readers • 292 pages • 3.6
1979 • 2,031 Readers • 215 pages • 4.3
1980 • 4 Readers • 271 pages • 4.3