United States. Bureau of the Census. "Foreign Trade," in United States. Bureau of the Census. "July 1969," Business Conditions Digest (July 1969) : 52-52. https://fraser.stlouisfed.org/title/43/item/7532/toc/358105 , accessed on April 25, 2024.
United States. Bureau of the Census. "Foreign Trade," in United States. Bureau of the Census. "July 1969," Business Conditions Digest (July 1969) : 52-52. https://fraser.stlouisfed.org/title/43/item/7532/toc/358105 , accessed on April 25, 2024.