REMOVE

1. plants
2. railroads
3. sky
4. houses
5. trains (vehicle groupings)
6. 1920

WHAT

1. Visual Works (hierarchy n … (1)
2. black-and-white film (1)
3. buildings (structures) (1)
4. exterior views (1)
5. fences (1)

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WHERE

1. Killam, Alberta, Canada (1)

WHO

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

WHEN

1. 1940 (1)
2. between 1920 - 1940 (1)