United States. Department of the Treasury. "Treasury's Weekly Bill Offering, June 18, 1991, Release Number nb-1333," in United States. Department of the Treasury. "Volume 308," Press Releases of the United States Department of the Treasury (June 3, 1991 - July 19, 1991) : 260-263. https://fraser.stlouisfed.org/title/6111/item/587151/toc/545961 , accessed on May 18, 2024.