United States. Department of the Treasury. "Treasury Offers Additional $1-3/4 Billion in June Tax Bills, January 8, 1969," in United States. Department of the Treasury. "Volume 163," Press Releases of the United States Department of the Treasury (October 1, 1968 - January 20, 1969) : 586-588. https://fraser.stlouisfed.org/title/6111/item/587006/toc/541281 , accessed on June 23, 2024.