REMOVE

1. machinery
2. rivers
3. trees
4. rubbish
5. 1936

WHAT

1. Visual Works (hierarchy n … (1)
2. automobiles (1)
3. buildings (structures) (1)
4. bushes (1)
5. campuses (1)

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WHERE

1. San Francisco, California (1)

WHO

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

WHEN

1. 1971 (1)
2. ca. 1971 (1)