REMOVE

1. clouds
2. utility poles
3. houses
4. sky
5. landscapes (representations)
6. Maryland

WHAT

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

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WHEN

1. 1961 (1)
2. after 1961 (1)