This Book is referred to by Mostly Harmless written by Douglas Adams
part of The Hitchhiker's Guide to
The Hitchhiker's Guide to the Galaxy is a fictional electronic guide book in the multimedia scifi/comedy series of the same name by Douglas Adams. The Guide serves as "the standard repository for all knowledge and wisdom" for many members of the series' galaxy-spanning civilization. Entries from the guidebook are used as comic narration to bridge events and provide background information in every version of the story. The guide is published by "Megadodo Publications", a publishing company on Ursa Minor Beta.