REMOVE

1. railroads
2. sky
3. platforms (general)

WHAT

1. Visual Works (hierarchy n … (1)
2. atmospheric perspective (1)
3. automobiles (1)
4. black-and-white film (1)
5. buildings (structures) (1)

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WHERE

1. 48 Cooper Square, New Yor … (1)

WHO

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

WHEN

1. 1952 (1)
2. ca. 1952 (1)