REMOVE

1. rivers
2. sky
3. fences
4. machinery
5. automobiles

WHAT

1. Visual Works (hierarchy n … (1)
2. black-and-white film (1)
3. farms (1)
4. fields (land) (1)

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WHO

1. Clyfford Still; Still, Cl … (1)
2. Still, Clyfford (1)

WHEN

1. 1920 (1)
2. 1940 (1)
3. between 1920 - 1940 (1)