REMOVE

1. paths
2. athletes
3. spectators (event observers)
4. barriers

WHAT

1. Visual Works (hierarchy n … (1)
2. automobiles (1)
3. black-and-white film (1)

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WHERE

1. Aiken, South Carolina (1)

WHO

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

WHEN

1. 1966 (1)