United States. Bureau of the Census. "NBER Short List," in United States. Bureau of the Census. "March 1970," Business Conditions Digest (March 1970) : 42-45. https://fraser.stlouisfed.org/title/43/item/7540/toc/227152 , accessed on May 4, 2024.
United States. Bureau of the Census. "NBER Short List," in United States. Bureau of the Census. "March 1970," Business Conditions Digest (March 1970) : 42-45. https://fraser.stlouisfed.org/title/43/item/7540/toc/227152 , accessed on May 4, 2024.