Board of Governors of the Federal Reserve System (U.S.), 1935-. "Gross public debt of the U.S. Treasury-Types and ownership," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "1980-1989," Annual Statistical Digest (March 1991) : 190-192. https://fraser.stlouisfed.org/title/7/item/23495/toc/414289 , accessed on May 8, 2024.