A rare double-sided illustration by Austrian painter Gustav Klimt has been found at Los Angeles gallery the Lost Art Salon.

Klimt is best known for his painting The Kiss (1908-1909)

It was discovered amid a collection of papers acquired in an auction and has since been identified as a study for his Portrait of Sonja Knips (1898).

Rob Delamater, one of the owners of the gallery, commented: "Frequently, as owners of the Lost Art Salon, we are asked, "what is your greatest discovery.

"The pieces featured in 'Time Capsule: A Lost Klimt and Other Viennese Treasures' constitute our most stunning and historically significant discoveries to date."

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