United States. Bureau of the Census. "NBER Short List," in United States. Bureau of the Census. "April 1971," Business Conditions Digest (April 1971) : 42-45. https://fraser.stlouisfed.org/title/43/item/7553/toc/368666 , accessed on April 26, 2024.
United States. Bureau of the Census. "NBER Short List," in United States. Bureau of the Census. "April 1971," Business Conditions Digest (April 1971) : 42-45. https://fraser.stlouisfed.org/title/43/item/7553/toc/368666 , accessed on April 26, 2024.