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 1941," Federal Reserve Bulletin (March 1941) : 68-68. https://fraser.stlouisfed.org/title/62/item/21035/toc/230684 , accessed on April 26, 2024.