Series: Hitchhiker series
The hitchhiker's guide to the galaxy (Volume 0001)
The restaurant at the end of the universe (Volume 0002)
Life, the universe, and everything (Volume 0003)
So long, and thanks for all the fish (Volume 0004)
Mostly harmless (Volume 0005)
And another thing--: Douglas Adams's Hitchhiker's guide to the galaxy, part six of three (Volume 0006)