United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "July 1969," Business Conditions Digest (July 1969) : 40-41. https://fraser.stlouisfed.org/title/43/item/7532/toc/358101 , accessed on March 28, 2024.
United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "July 1969," Business Conditions Digest (July 1969) : 40-41. https://fraser.stlouisfed.org/title/43/item/7532/toc/358101 , accessed on March 28, 2024.