Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "Kinds of United States Currency Outstanding and in Circulation," in Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "May 1961," Federal Reserve Bulletin (May 1961) : 44-44. https://fraser.stlouisfed.org/title/62/item/21317/toc/52808 , accessed on May 4, 2024.