United States. Bureau of Economic Analysis. "April 1927," Survey of Current Business (April 1927). https://fraser.stlouisfed.org/title/46/item/9212, accessed on March 28, 2024.
United States. Bureau of Economic Analysis. "April 1927," Survey of Current Business (April 1927). https://fraser.stlouisfed.org/title/46/item/9212, accessed on March 28, 2024.