Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "Freight-Car Loadings, by Classes," in Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "February 1940," Federal Reserve Bulletin (February 1940) : 76-76. https://fraser.stlouisfed.org/title/62/item/21022/toc/431963 , accessed on April 26, 2024.