Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "Mortgage Debt Outstanding," in Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "January 1973," Federal Reserve Bulletin (January 1973) : 102-102. https://fraser.stlouisfed.org/title/62/item/21458/toc/53132 , accessed on April 23, 2024.