United States. Bureau of the Census. "Gross National Product," in United States. Bureau of the Census. "May 1975," Business Conditions Digest (May 1975) : 35-35. https://fraser.stlouisfed.org/title/43/item/7345/toc/405856 , accessed on May 5, 2024.
United States. Bureau of the Census. "Gross National Product," in United States. Bureau of the Census. "May 1975," Business Conditions Digest (May 1975) : 35-35. https://fraser.stlouisfed.org/title/43/item/7345/toc/405856 , accessed on May 5, 2024.