REMOVE

1. landscapes (representations)
2. railroads
3. Lake Louise, Alberta, Canada

WHAT

1. exterior views (1)
2. forests (plant communitie … (1)
3. mountains (1)
4. railroad stations (1)

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WHO

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

WHEN

1. 1920 (1)
2. 1945 (1)
3. between circa 1929 and ci … (1)