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. "March 1937," Federal Reserve Bulletin (March 1937) : 93-93. https://fraser.stlouisfed.org/title/62/item/20740/toc/70944 , accessed on May 4, 2024.