REMOVE

1. portraits
2. hats
3. black-and-white film
4. groves (plant communities)

WHAT

1. Visual Works (hierarchy n … (1)
2. artists (visual artists) (1)
3. automobiles (1)
4. branches (plant component … (1)

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WHEN

1. 1960 (1)
2. 1970 (1)
3. between 1960 - 1970 (1)