United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "March 1970," Business Conditions Digest (March 1970) : 1-1. https://fraser.stlouisfed.org/title/43/item/7540/toc/227127 , accessed on April 27, 2024.
United States. Bureau of the Census. "Cover Page," in United States. Bureau of the Census. "March 1970," Business Conditions Digest (March 1970) : 1-1. https://fraser.stlouisfed.org/title/43/item/7540/toc/227127 , accessed on April 27, 2024.