United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "April 1977," Business Conditions Digest (April 1977) : 1-1. https://fraser.stlouisfed.org/title/43/item/7368/toc/49184 , accessed on May 1, 2024.
United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "April 1977," Business Conditions Digest (April 1977) : 1-1. https://fraser.stlouisfed.org/title/43/item/7368/toc/49184 , accessed on May 1, 2024.