REMOVE

1. houses
2. railroads
3. authors
4. American

WHAT

1. Visual Works (hierarchy n … (1)
2. bridges (built works) (1)
3. buildings (structures) (1)
4. civil wars (1)
5. color film (film) (1)

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WHERE

1. Harpers Ferry, West Virgi … (1)

WHO

1. Still, Patricia (1)

WHEN

1. 1973 (1)
2. 1973 September 13 (1)