American
Hybrid
Sub-Total
Peace Through Chemistry I
Red-Orange Yellow Blue
Grid Stack
Green Black
Blue White Red
, 1969
, 1970
, 1971
![Bent "Blue" [trial proof]](https://api.nga.gov/iiif/0897b9bd-7a5c-4315-b3e0-da35c5fc8db7/full/843,/0/default.jpg)
![Delaware Crossing [color trial proof]](https://api.nga.gov/iiif/671ce331-d8cb-47c1-a606-594828a245d4/full/843,/0/default.jpg)
![Delaware Crossing [color trial proof]](https://api.nga.gov/iiif/e9a5612d-0efc-4b70-9b81-e99b1d2f5371/full/843,/0/default.jpg)
![Untitled [working proof]](https://api.nga.gov/iiif/e74ddd17-dc42-4043-b220-7e1ef87f77d9/full/843,/0/default.jpg)
![Delaware Crossing [color trial proof]](https://api.nga.gov/iiif/2ff91d54-7f72-4d2a-a26a-cf3b4aa79feb/full/843,/0/default.jpg)
![Delaware Crossing [color trial proof]](https://api.nga.gov/iiif/26731a48-174e-4989-af74-301c95760617/full/843,/0/default.jpg)
![Untitled [trial proof]](https://api.nga.gov/iiif/3e2e1a28-21b4-4ae7-b8f6-a41abc6520d2/full/843,/0/default.jpg)
![Delaware Crossing [color trial proof]](https://api.nga.gov/iiif/0fc75009-e3a8-42bd-8f95-8abb502b1043/full/843,/0/default.jpg)