United States. Department of the Treasury. "Weekly Bill Results, December 11, 1972," in United States. Department of the Treasury. "Volume 181," Press Releases of the United States Department of the Treasury (October 2, 1972 - December 29, 1972) : 529-532. https://fraser.stlouisfed.org/title/6111/item/587024/toc/542867 , accessed on June 25, 2024.