1971
Ronald Davis, 1975
James Webb, 1973
Gemini G.E.L., 1973
Gemini G.E.L., 1978
Gemini G.E.L., 1980
Gemini G.E.L., 1977
James Webb, 1969
Gemini G.E.L., 1991
Gemini G.E.L., 1992
Gemini G.E.L., 1999
![Knee [trial proof]](https://api.nga.gov/iiif/fdb17cd2-18fd-4429-a4ac-a12debaa49af/full/843,/0/default.jpg)
![Four Panels from Untitled 1972 [D panel, trial proof 26]](https://api.nga.gov/iiif/7be8b383-9e4d-43a6-8384-53a544d0c3bc/full/843,/0/default.jpg)
![0 through 9 [trial proof]](https://api.nga.gov/iiif/01755a16-93b0-4793-8e71-7569bbb518a7/full/843,/0/default.jpg)
![Figure 0 [trial proof]](https://api.nga.gov/iiif/8fbdb5e2-560b-4bfa-bc50-4437f727639f/full/843,/0/default.jpg)
