Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "Initial Margin Requirements Under Regulations T, U, and X," in Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "2020," Annual Report of the Board of Governors of the Federal Reserve System (2020) : 228-228. https://fraser.stlouisfed.org/title/117/item/604946/toc/591675 , accessed on July 19, 2024.