United States. Bureau of Economic Analysis. "February 1930," Survey of Current Business (February 1930). https://fraser.stlouisfed.org/title/46/item/9246, accessed on June 21, 2024.
United States. Bureau of Economic Analysis. "February 1930," Survey of Current Business (February 1930). https://fraser.stlouisfed.org/title/46/item/9246, accessed on June 21, 2024.