Scale ca. 1:510,000. Includes "Counties" index. Available also through the Library of Congress Web site as a raster image. AACR2
United States. Bureau Of The Census
1971
<a rel="nofollow" class="external free" href="https://www.loc.gov/item/gm72003039/">https://www.loc.gov/item/gm72003039/</a>