Images:
1. Harmensz van Rijn Rembrandt, Self-Portrait, c. 1628, Rijksmuseum, Amsterdam .
2. Pablo Picasso, Acrobat on a Ball, 1905, Pushkin Museum of Fine Art
3. Edvard Munch, Puberty, 1894-1895, National Gallery, Oslo
4. Pablo Picasso, Girl Before a Mirror, 1932, Museum of Modern Art, NY