United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "January 1970," Business Conditions Digest (January 1970) : 1-1. https://fraser.stlouisfed.org/title/43/item/7538/toc/341727 , accessed on April 23, 2024.
United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "January 1970," Business Conditions Digest (January 1970) : 1-1. https://fraser.stlouisfed.org/title/43/item/7538/toc/341727 , accessed on April 23, 2024.