"March 1980 4-R-37394. March 1980 base 4-R-34039-1." "Compiled from 1:250,000 USGS map sheets." "Plate A-3." Shows regions of outer and inner blue grass, eastern coal field, and knobs and escarpment. Includes location map. Available also through the Library of Congress Web site as a raster image.
United States. Soil Conservation Service
1980
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