United States. Bureau of the Census. "Title Page," in United States. Bureau of the Census. "July 1981," Business Conditions Digest (July 1981) : 2-2. https://fraser.stlouisfed.org/title/43/item/7419/toc/226032 , accessed on May 4, 2024.
United States. Bureau of the Census. "Title Page," in United States. Bureau of the Census. "July 1981," Business Conditions Digest (July 1981) : 2-2. https://fraser.stlouisfed.org/title/43/item/7419/toc/226032 , accessed on May 4, 2024.