REMOVE

1. roads
2. trees
3. houses
4. Alberta, Canada

WHAT

1. Visual Works (hierarchy n … (1)
2. exterior views (1)
3. fields (land) (1)
4. grain elevators (1)

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WHO

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

WHEN

1. 1920 (1)
2. 1945 (1)
3. between circa 1929 and ci … (1)