Man Ray's iconic poster for the London Underground is to feature in a sale of vintage posters at Christie's on May 21.
The lot, titled Keeps London Going (1939), is valued at £40,000-60,000 ($66,880-100,500).
Ray (1890-1976) created the image using his photogram technique, which involves placing objects on photographic paper and exposing them to light.
The work is one of a number of increasingly avant-garde works created for the London Underground during the 1920s and 1930s.
In 2007, another example of the poster sold for £50,400 ($100,901) at Christie's in London, a new world record for a travel poster at auction.
Another advertisement for the service - Edward McKnight Kauffer's Power, The Nerve Centre of London's Underground (1930) - is valued at £30,000-40,000 ($50,160-66,880).
Kauffer (1890-1954) was an American-born artist and designer who moved to Britain in 1914.
He produced around 140 posters for the Underground that draw influence from styles as diverse as vorticism and impressionism.
An advertisement for Rezinotrest galoshes (1923) by Alexander Rodchenko, with text by the playwright and poet Vladimir Mayakovsky, carries an identical estimate of £30,000-40,000 ($50,160-66,880).
Another advert by Rodchenko, this time for the Dobrolet air fleet, will auction on April 24 at Swann Auction Galleries.
You can check out our collection of vintage posters here.
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