United States. Bureau of the Census. "Table of Contents," in United States. Bureau of the Census. "May 1975," Business Conditions Digest (May 1975) : 3-4. https://fraser.stlouisfed.org/title/43/item/7345/toc/405849 , accessed on April 25, 2024.
United States. Bureau of the Census. "Table of Contents," in United States. Bureau of the Census. "May 1975," Business Conditions Digest (May 1975) : 3-4. https://fraser.stlouisfed.org/title/43/item/7345/toc/405849 , accessed on April 25, 2024.