United States. Bureau of the Census. "Foreign Trade," in United States. Bureau of the Census. "April 1975," Business Conditions Digest (April 1975) : 19-19. https://fraser.stlouisfed.org/title/43/item/7344/toc/176677 , accessed on June 30, 2024.
United States. Bureau of the Census. "Foreign Trade," in United States. Bureau of the Census. "April 1975," Business Conditions Digest (April 1975) : 19-19. https://fraser.stlouisfed.org/title/43/item/7344/toc/176677 , accessed on June 30, 2024.