Upright Slab1975 · Color aquatint, etching, drypoint and engraving on white wove paper, with colored pulp additions60.3 × 50 cm (23 3/4 × 19 11/16 in.)Art Institute of Chicago
Turn (2/3)1968 · Fiberglass and polyester resin152.4 × 365.7 cm (60 × 144 in.)Art Institute of Chicago