United States. Bureau of the Census. "Aggregate Series," in United States. Bureau of the Census. "April 1974," Business Conditions Digest (April 1974) : 49-51. https://fraser.stlouisfed.org/title/43/item/7332/toc/263409 , accessed on April 19, 2024.
United States. Bureau of the Census. "Aggregate Series," in United States. Bureau of the Census. "April 1974," Business Conditions Digest (April 1974) : 49-51. https://fraser.stlouisfed.org/title/43/item/7332/toc/263409 , accessed on April 19, 2024.