London: The authorised biography of Sir V.S. Naipaul that said his infidelity and mental cruelty may have contributed to his wife's death is tipped to win the richest prize in non-fiction writing.

Patrick French's "The World is What it is: The Authorized Biography of V.S. Naipaul" heads the shortlist for the 30,000 pounds Samuel Johnson prize, to be announced July 15.

Bookies William Hill have French's book at 5-2, followed by "The Suspicions of Mr Whicher: Or the Murder at Road Hill House" by Kate Summerscale (3-1); "The Whisperers" by Orlando Figes and "Blood River: A Journey to Africa's Broken Heart" by Tim Butcher (both 4-1); "Crow Country" by Mark Cocker (5-1); and "The Rest is Noise" by Alex Ross (6-1).

The book on Naipaul says the Nobel laureate had a 24-year affair with an Argentinian lover in the full knowledge of his wife Pat and visited prostitutes while she was alive.

A day after cremating Pat in 1996 he welcomed into his home a Pakistani journalist he had recently met - and they married two months later.

Journalist Rosie Boycott, who is chairing the judging panel, said: “All six books are ones which changed the way we looked at the world, they are all ones we are eager to pass on to others.�