Arthur C. Clarke,

Childhood’s End , Ballantine, New York, 1953

Brian Clegg,

Light Years and Time Travel , Wiley, New York, 2001

The Runaway Universe , HarperCollins, London, 1978

About Time , Viking, London, 1995

David Deutsch,

The Fabric of Reality , Allen Lane, London, 1997

The Man in the High Castle , Gollancz, London, 1975

Counter-Clock World , Berkley Medallion, NewYork, 1967

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