REMOVE

1. roads
2. automobiles
3. hills
4. pipes (conduits)
5. 1920
6. 1945

WHAT

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

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WHERE

1. Alberta, Canada (1)

WHO

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

WHEN

1. between circa 1929 and ci … (1)