REMOVE

1. benches (furniture)
2. stairs
3. fedoras
4. libraries (buildings)

WHAT

1. Visual Works (hierarchy n … (1)
2. arcades (structural assem … (1)
3. artists (visual artists) (1)
4. barriers (1)

More 

WHERE

1. New York, New York (1)

WHEN

1. 1964 (1)
2. ca. 1964 (1)