1967
Gemini G.E.L., 1967
Gemini G.E.L., 1968
Gemini G.E.L., 1971
Gemini G.E.L., 1966
Dan Gualdoni, 1969
Gemini G.E.L., 1970
Charles Ritt, 1971
Gemini G.E.L., 1976
![Figure 6 [trial proof]](https://api.nga.gov/iiif/99d11251-16e4-45a2-becd-ca218d8c460b/full/843,/0/default.jpg)
![Delaware Crossing [color trial proof]](https://api.nga.gov/iiif/6b380faa-3752-4b9a-b576-7e8a277615fc/full/843,/0/default.jpg)
![Coathanger and Spoon [trial proof]](https://api.nga.gov/iiif/b83ef090-d42f-4d87-913b-c375906c78be/full/843,/0/default.jpg)
![#6 (after 'Untitled 1975') [progressive proof 15]](https://api.nga.gov/iiif/55152616-bdc8-4db4-94d1-fffd9fee52f0/full/843,/0/default.jpg)