1949. Geological Survey (U.S.). Contour interval 10 feet.;"Culture and drainage in part compiled from aerial photographs taken 1939. Topography by plane-table methods 1946.";Relie... Geological Survey (U.S.) and Geological Survey Division (Urbana, Ill.).
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1949. Geological Survey (U.S.). Contour interval 10 feet;"Culture and drainage in part compiled from aerial photographs taken 1938. Topography by plane-table methods 1947.";Relief... Geological Survey (U.S.) and Geological Survey Division (Urbana, Ill.).