REMOVE

1. cans (containers)
2. black-and-white film
3. shadows
4. paintings (visual works)

WHAT

1. Visual Works (hierarchy n … (1)
2. artists (visual artists) (1)
3. artists' materials (1)
4. barns (1)
5. beards (1)

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WHO

1. Campbell, Sandra L. Still (1)
2. Sandra L. Still Campbell; … (1)

WHEN

1. 1973 (1)
2. ca. 1973 (1)