United States. Department of the Treasury. "Bill tender on March Tax bills (248-day tax bills), July 11, 1969," in United States. Department of the Treasury. "Volume 165," Press Releases of the United States Department of the Treasury (May 6, 1969 - August 29, 1969) : 289-290. https://fraser.stlouisfed.org/title/6111/item/587008/toc/541491 , accessed on June 22, 2024.