United States. Bureau of the Census. "Foreign Trade," in United States. Bureau of the Census. "July 1977," Business Conditions Digest (July 1977) : 51-51. https://fraser.stlouisfed.org/title/43/item/7371/toc/219056 , accessed on April 18, 2024.
United States. Bureau of the Census. "Foreign Trade," in United States. Bureau of the Census. "July 1977," Business Conditions Digest (July 1977) : 51-51. https://fraser.stlouisfed.org/title/43/item/7371/toc/219056 , accessed on April 18, 2024.