United States. Bureau of the Census. "Aggregate Series," in United States. Bureau of the Census. "August 1969," Business Conditions Digest (August 1969) : 46-48. https://fraser.stlouisfed.org/title/43/item/7533/toc/216365 , accessed on May 9, 2024.
United States. Bureau of the Census. "Aggregate Series," in United States. Bureau of the Census. "August 1969," Business Conditions Digest (August 1969) : 46-48. https://fraser.stlouisfed.org/title/43/item/7533/toc/216365 , accessed on May 9, 2024.