United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "February 1981," Business Conditions Digest (February 1981) : 1-1. https://fraser.stlouisfed.org/title/43/item/7414/toc/32878 , accessed on July 14, 2024.
United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "February 1981," Business Conditions Digest (February 1981) : 1-1. https://fraser.stlouisfed.org/title/43/item/7414/toc/32878 , accessed on July 14, 2024.