Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "National Summary of Business Conditions," in Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "April 1940," Federal Reserve Bulletin (April 1940) : 42-43. https://fraser.stlouisfed.org/title/62/item/21024/toc/392495 , accessed on April 16, 2024.