REMOVE

1. sidewalks
2. sky
3. colleges (buildings)
4. windows
5. black-and-white film
6. 1950

WHAT

1. Visual Works (hierarchy n … (1)
2. buildings (structures) (1)
3. 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. 1946 (1)
2. between 1946 - 1950 (1)