Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "Estimated Foreign Holdings of Marketable U.S. Government Bonds and Notes," in Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "July 1968," Federal Reserve Bulletin (July 1968) : 202-202. https://fraser.stlouisfed.org/title/62/item/21403/toc/144055 , accessed on June 27, 2024.