REMOVE

1. rail transit systems
2. buildings (structures)
3. automobiles
4. exterior views

WHAT

1. New York, New York (1)
2. Visual Works (hierarchy n … (1)

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WHO

1. Clyfford Still; Still, Cl … (1)
2. Still, Clyfford (1)

WHEN

1. 1950 (1)
2. 1954 (1)
3. Early 1950s (1)