Robert Ryman /Works and biography    Untitled, 1973 Double-baked enamel on raw copper, 5 panels, each: 40.6 x 40.6 cm Solomon R. Guggenheim Foundation, Hannelore B. and Rudolph B. Schulhof Collection, bequest of Hannelore B. Schulhof, 2012 2012.93 credits: Hangar Design Group