United States. Bureau of the Census. "Leading Indicators," in United States. Bureau of the Census. "June 1967," Business Conditions Digest (June 1967) : 17-24. https://fraser.stlouisfed.org/title/43/item/7240/toc/196632 , accessed on March 28, 2024.
United States. Bureau of the Census. "Leading Indicators," in United States. Bureau of the Census. "June 1967," Business Conditions Digest (June 1967) : 17-24. https://fraser.stlouisfed.org/title/43/item/7240/toc/196632 , accessed on March 28, 2024.