Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "Crude Petroleum," in Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "December 1920," Federal Reserve Bulletin (December 1920) : 87-87. https://fraser.stlouisfed.org/title/62/item/20608/toc/344418 , accessed on April 19, 2024.