United States. Bureau of the Census. "Method of Presentation," in United States. Bureau of the Census. "June 1972," Business Conditions Digest (June 1972) : 7-10. https://fraser.stlouisfed.org/title/43/item/7567/toc/381399 , accessed on May 4, 2024.
United States. Bureau of the Census. "Method of Presentation," in United States. Bureau of the Census. "June 1972," Business Conditions Digest (June 1972) : 7-10. https://fraser.stlouisfed.org/title/43/item/7567/toc/381399 , accessed on May 4, 2024.