Nu (Carmelita) by French Artist Henri Matisse c1904

Henri-Émile-Benoît Matisse (31 December 1869 – 3 November 1954) was a French artist, known for his use of colour and his fluid and original draughtsmanship. He was a draughtsman, printmaker, and sculptor, but is known primarily as a painter. Matisse is commonly regarded, along with Pablo Picasso and Marcel Duchamp, as one of the three artists who helped to define the revolutionary developments in the plastic arts in the opening decades of the twentieth century.
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The Virgin of the Rocks (Louvre Version) by Leonardo da Vinci c1485

The Virgin of the Rocks (sometimes the Madonna of the Rocks) is the name used for two paintings by Leonardo da Vinci, of the same subject, and of a composition which is identical except for several significant details. The version generally considered the prime version, that is the earlier of the two, hangs in The Louvre in Paris and the other in the National Gallery, London. The paintings are both nearly 2 metres (over 6 feet) high and are painted in oils. Both were painted on wooden panel; that in the Louvre has been transferred to canvas.
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The Lady with the Ermine (Cecilia Gallerani) by Leonardo da Vinci c1490

Lady with an Ermine is a painting by Leonardo da Vinci from around 1489–1490. The subject of the portrait is Cecilia Gallerani, and probably was painted at a time when she was the mistress of Ludovico Sforza, Duke of Milan, and Leonardo was in the service of the Duke. The painting is one of only four portraits of women painted by Leonardo, the others being the Mona Lisa, the portrait of Ginevra de' Benci, and La belle ferronnière. It is currently displayed at the Wawel Castle, Kraków, Poland.
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Madonna with a Flower (Madonna Benois) by Leonardo da Vinci c1478