REMOVE

1. sidewalks
2. sky
3. Alberta, Canada
4. 1920

WHAT

1. Visual Works (hierarchy n … (1)
2. automobiles (1)
3. buildings (structures) (1)
4. exterior views (1)
5. fences (1)

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WHO

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

WHEN

1. 1945 (1)
2. between circa 1929 and ci … (1)