REMOVE

1. trees
2. sidewalks
3. sky
4. bushes
5. exterior views
6. colleges (buildings)

WHAT

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