An employee poses for photographers in front of Pablo Picasso's ''Tete de femme'' painting at Christie's auction house in London. REUTERS/Stefan Wermuth LONDON (REUTERS).- Pablo Picasso once again proved his appeal to wealthy collectors when the artist's...

Kees van Dongem (1877-1968), "Gitane", circa 1910-1911, signed 'van Dongen' on the lower right. Oil on canvas, (100.2 x 81.2 cm.) 39.3/8 x 32 inches. Estimate: £5,500,000-7,500,000. Photo: Christie's Images Ltd., 2010 LONDON.- The Impressionist and Modern...