REMOVE

1. sky
2. soil
3. roads
4. barriers
5. Grand Coulee Dam (dam)

WHAT

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

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WHERE

1. Nespelem, Washington (1)

WHO

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

WHEN

1. 1937 (1)
2. 1938 (1)
3. ca. 1937 - 1938 (1)