United States. Bureau of the Census. "September 1977," Business Conditions Digest (September 1977). https://fraser.stlouisfed.org/title/43/item/7373, accessed on April 19, 2024.
United States. Bureau of the Census. "September 1977," Business Conditions Digest (September 1977). https://fraser.stlouisfed.org/title/43/item/7373, accessed on April 19, 2024.