United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "September 1975," Business Conditions Digest (September 1975) : 1-1. https://fraser.stlouisfed.org/title/43/item/7349/toc/350131 , accessed on April 19, 2024.
United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "September 1975," Business Conditions Digest (September 1975) : 1-1. https://fraser.stlouisfed.org/title/43/item/7349/toc/350131 , accessed on April 19, 2024.