REMOVE

1. valleys (landforms)
2. rivers
3. banks (landforms)
4. 1925

WHAT

1. Visual Works (hierarchy n … (1)
2. black-and-white film (1)
3. branches (plant component … (1)
4. bridges (built works) (1)

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WHERE

1. Spokane, Washington (1)

WHO

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

WHEN

1. ca. 1925 (1)