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Museum Folkwang Essen / ARTOTHEK
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Courtesy Metropolitan Museum, New York (Sabine Rewald)
Berlin, Archiv Wolfgang Wittrock
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Columbus Museum of Art
Archiv Eigentümer(in) / Owner’s Archive. Foto: Peter Schälchli, Zürich
Collection Albright-Knox Art Gallery, Buffalo, New York. Room of Contemporary Art Fund, 1950 (RCA1950:1). Foto: Tom Loonan