1971
Gemini G.E.L., 1969
Gemini G.E.L., 1999
Gemini G.E.L., 1976
Benjamin B. Smith, 1972
Josef Albers
Josef Albers, 1972
Ron McPherson, 1983
Josef Albers, 1962
Gemini G.E.L., 1980
Gemini G.E.L., 2002
Ron McPherson, 1978
![#6 (after 'Untitled 1975') [progressive proof 2]](https://api.nga.gov/iiif/21449e8a-3c47-418e-bdd1-e1f01ce02806/full/843,/0/default.jpg)
![Celia Pondering [special proof]](https://api.nga.gov/iiif/f22d6731-1a24-4f09-b9e0-f147ce3f9661/full/843,/0/default.jpg)
![Untitled (Web 4) [special proof]](https://api.nga.gov/iiif/ff98802d-4ecd-4ff0-a061-982822fe71f4/full/843,/0/default.jpg)
