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 1951," Federal Reserve Bulletin (February 1951) : 87-87. https://fraser.stlouisfed.org/title/62/item/21194/toc/60853 , accessed on April 23, 2024.