United States. Bureau of the Census. "Table of Contents," in United States. Bureau of the Census. "April 1977," Business Conditions Digest (April 1977) : 3-4. https://fraser.stlouisfed.org/title/43/item/7368/toc/49186 , accessed on April 17, 2024.
United States. Bureau of the Census. "Table of Contents," in United States. Bureau of the Census. "April 1977," Business Conditions Digest (April 1977) : 3-4. https://fraser.stlouisfed.org/title/43/item/7368/toc/49186 , accessed on April 17, 2024.