We are also looking at his PC to see how much he had completed of the novel he was working on when he died

Ed Victor, Literary agent

According to the Independent on Sunday, the collection will contain The Salmon of Doubt - an unfinished new novel - and the screenplay to the proposed film of The Hitch Hiker's Guide To The Galaxy.

Adams died last month in California following a heart attack. He was 49.

He became a household name when the cult science fiction novel, itself based on a BBC radio show, was turned into a BBC TV series.

Hitch Hikers Guide was turned into a BBC series

Publishers Pan are scanning the writer's personal computer to piece together his final novel. A number of e-mail essays will also be published.

Adams' literary agent, Ed Victor, told the Independent on Sunday: "The book will focus on writing that has never been published or only partly published before now.

"This is likely to include Douglas's screenplay for the Hitch Hiker's film, which is still in 'development hell' at the moment, and we are also looking at his PC to see how much he had completed of the novel he was working on when he died."

He added that there was no question of any other writer completing the book.

Life, the universe and everything

Adams was born in Cambridge in 1952 and educated in Essex before returning to Cambridge to study at St John's College.

Arthur Dent and Slartibartfast became cult figures

His career included work as a radio and television writer - including the BBC's Doctor Who - and producer before his life was changed by the publication of The Hitchhiker's Guide to the Galaxy in 1979.

The satirical tale chronicled the journey of alien Ford Prefect and his human companion Arthur Dent throughout the Universe after the destruction of Earth.

It centred around the search for an answer to life, the universe, and everything - which turned out to be 42.

The novel went on to sell more than 14 million copies worldwide and was followed by the sequels The Restaurant at the End of the Universe; Life, the Universe and Everything; So Long and Thanks For All the Fish and Mostly Harmless.

A memorial event is being planned for the author in London in September.