United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "August 1969," Business Conditions Digest (August 1969) : 40-41. https://fraser.stlouisfed.org/title/43/item/7533/toc/216363 , accessed on May 9, 2024.
United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "August 1969," Business Conditions Digest (August 1969) : 40-41. https://fraser.stlouisfed.org/title/43/item/7533/toc/216363 , accessed on May 9, 2024.