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New York, Neue Galerie

Düren, Leopold Hoesch Museum. Foto: Aachen, Peter Hinschläger

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Christie's Images Ltd / ARTOTHEK

Washington D. C., Smithsonian Institution, Hirshorn Museum and Sculpture Garden. Gift of the Joseph H. Hirshhorn Foundation, 1966. Foto: Lee Stalsworth

Saint Louis Art Museum, Bequest of Morton D. May 867:1983