Douglas Adams, The Original Hitchhiker Radio Scripts, edited by Geoffrey Perkins, Harmony Books, 1985.

This book contains the scripts for the original radio show on which the novel was based; an introduction in which Adams talks about his writing; another introduction by the producer of the show, Geoffrey Perkins; and many notes about the script.

Brian W. Aldiss, introduction to Hell's Cartographers: Some Personal Histories of Science Fiction Writers, edited by Brian W. Aldiss and Harry Harrison, Weidenfeld and Nicolson, 1975, pp. 1-5.

Aldiss discusses the effect that the dropping of the first atomic bomb on Hiroshima had on science fiction and science fiction writers.

Thomas M. Disch, The Dreams Our Stuff Is Made of: How Science Fiction Conquered the World,The Free Press, 1998.

To understand how well The Hitchhiker's Guide to the Galaxy parodies the science fiction tradition, and how much it follows the rules that...