United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "May 1977," Business Conditions Digest (May 1977) : 1-1. https://fraser.stlouisfed.org/title/43/item/7369/toc/321278 , accessed on April 19, 2024.
United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "May 1977," Business Conditions Digest (May 1977) : 1-1. https://fraser.stlouisfed.org/title/43/item/7369/toc/321278 , accessed on April 19, 2024.