Without knowing who has created the works, people can bid for them on eBay until the auction, called The Big Art Secret, closes on Sunday. Proceeds from the sale will go to St Wilfrid's Hospice. Hockney's work is "an ink and colour crayon drawing on a postcard" and Emin has donated four postcards.
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Former One Direction star Harry Styles and Hollywood actor Tom Hardy have been in Dorset for filming of their new blockbuster Dunkirk.
Amanda Houston has the latest forecast for the west of the ITV Meridian region
Amanda Houston has the latest forecast for the east of the ITV Meridian region