United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "October 1968," Business Conditions Digest (October 1968) : 1-1. https://fraser.stlouisfed.org/title/43/item/7256/toc/360084 , accessed on April 25, 2024.
United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "October 1968," Business Conditions Digest (October 1968) : 1-1. https://fraser.stlouisfed.org/title/43/item/7256/toc/360084 , accessed on April 25, 2024.