United States. Department of the Treasury. "Treasury's Weekly Bill Offering, April 23, 1991, Release Number nb-1229," in United States. Department of the Treasury. "Volume 306," Press Releases of the United States Department of the Treasury (April 1, 1991 - May 13, 1991) : 110-113. https://fraser.stlouisfed.org/title/6111/item/587149/toc/545693 , accessed on May 18, 2024.