United States. Bureau of the Census. "NBER Short List," in United States. Bureau of the Census. "May 1970," Business Conditions Digest (May 1970) : 42-45. https://fraser.stlouisfed.org/title/43/item/7542/toc/272005 , accessed on March 29, 2024.
United States. Bureau of the Census. "NBER Short List," in United States. Bureau of the Census. "May 1970," Business Conditions Digest (May 1970) : 42-45. https://fraser.stlouisfed.org/title/43/item/7542/toc/272005 , accessed on March 29, 2024.