A photo of Pablo Picasso's painting, Head of a Young Woman, released by French authorities on Tuesday. The painting was seized from a yacht on July 31 in Corsica, France. The painting belongs to a Spanish billionaire who was planning to sell it elsewhere in Europe. But Spanish authorities say it is a "national treasure" that can't be sent abroad without government permission. Douane Francaise via AP hide caption

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The Picasso work Women of Algiers (Version O) was sold for a record-breaking $179,365,000 Monday by Christie's auction house, making it the most expensive painting ever sold. Andrew Burton/Getty Images hide caption

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Scientists and art experts found a hidden painting beneath one of Picasso's first masterpieces, The Blue Room, thanks to advances in infrared technology. Here, associate conservator Patricia Favero of The Phillips Collection points to a detail in the image. Evan Vucci/AP hide caption

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There's an empty space today where a Henri Matisse painting had been hanging at the Kunsthal museum in Rotterdam, Netherlands. Seven paintings were stolen Tuesday, including works by Pablo Picasso, Claude Monet and Paul Gauguin. Peter Dejong/AP hide caption

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