REMOVE

1. railroads
2. smoke
3. notes
4. farms
5. abstraction

WHAT

1. Visual Works (hierarchy n … (2)
2. automobiles (2)
3. black-and-white film (2)
4. bushes (2)
5. fences (2)

More 

WHERE

1. New Windsor, Maryland (1)
2. Westminster, Maryland (1)

WHO

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

WHEN

1. 1966 (2)
2. after 1966 (1)
3. ca. 1966 (1)