United States. Department of the Treasury. "Bill offering on $1 3/4 billion in September Tax Bills, March 13, 1970," in United States. Department of the Treasury. "Volume 168," Press Releases of the United States Department of the Treasury (February 2, 1970 - April 30, 1970) : 315-317. https://fraser.stlouisfed.org/title/6111/item/587011/toc/541703 , accessed on June 25, 2024.