Board of Governors of the Federal Reserve System (U.S.), 1935-. "Treasury Currency and SDR Certificates, Unadjusted Net Flows," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "March 11, 1988," Z.1 Financial Accounts of the United States (1988-03-11) : 42-42. https://fraser.stlouisfed.org/title/93/item/69079/toc/483859 , accessed on April 19, 2024.