United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "January 1969," Business Conditions Digest (January 1969) : 1-1. https://fraser.stlouisfed.org/title/43/item/7526/toc/343844 , accessed on April 23, 2024.
United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "January 1969," Business Conditions Digest (January 1969) : 1-1. https://fraser.stlouisfed.org/title/43/item/7526/toc/343844 , accessed on April 23, 2024.