Works from the art collection of bestselling US author Michael Crichton will be sold by Christie's in New York in May, the auctioneer said Friday. The collection includes “key” works by Pablo Picasso, Jasper Johns, Robert Rauschenberg and Roy Lichtenstein, and one painting by each artist will go on display at Christie's in London from Feb. 6-12. Although the auctioneer did not give an estimate of the value of the collection to be sold, the four exhibited works alone are expected to fetch around 20 million pounds ($32 million). One of the highlights is “Flag” by Johns, dated 1960-66, which Christie's described as a “painstakingly beautiful rendition of the American flag” which has never been on the public market. It added that flag paintings by Johns could be described as the first icons of pop art, ending the dominance of abstract expressionism practised by the likes of Jackson Pollock and Mark Rothko. Crichton died unexpectedly of cancer aged 66 in November, 2008. He was a medical doctor turned novelist and filmmaker whose books sold more than 150 million copies worldwide.