United States. Bureau of the Census. "Title Page," in United States. Bureau of the Census. "May 1966," Business Conditions Digest (May 1966) : 2-2. https://fraser.stlouisfed.org/title/43/item/7227/toc/383998 , accessed on April 19, 2024.
United States. Bureau of the Census. "Title Page," in United States. Bureau of the Census. "May 1966," Business Conditions Digest (May 1966) : 2-2. https://fraser.stlouisfed.org/title/43/item/7227/toc/383998 , accessed on April 19, 2024.