United States. Bureau of the Census. "Foreign Trade," in United States. Bureau of the Census. "December 1977," Business Conditions Digest (December 1977) : 87-87. https://fraser.stlouisfed.org/title/43/item/7376/toc/368013 , accessed on May 9, 2024.
United States. Bureau of the Census. "Foreign Trade," in United States. Bureau of the Census. "December 1977," Business Conditions Digest (December 1977) : 87-87. https://fraser.stlouisfed.org/title/43/item/7376/toc/368013 , accessed on May 9, 2024.