United States. Bureau of the Census. "Foreign Trade," in United States. Bureau of the Census. "June 1969," Business Conditions Digest (June 1969) : 72-72. https://fraser.stlouisfed.org/title/43/item/7531/toc/242256 , accessed on May 3, 2024.
United States. Bureau of the Census. "Foreign Trade," in United States. Bureau of the Census. "June 1969," Business Conditions Digest (June 1969) : 72-72. https://fraser.stlouisfed.org/title/43/item/7531/toc/242256 , accessed on May 3, 2024.