U.S. Savings Bonds Issued and Redeemed through August 31,1967, September 11, 1967
United States. Department of the Treasury. "U.S. Savings Bonds Issued and Redeemed through August 31,1967, September 11, 1967," in United States. Department of the Treasury. "Volume 159," Press Releases of the United States Department of the Treasury (September 1, 1967 - November 29, 1967) : 2-3. https://fraser.stlouisfed.org/title/6111/item/587002/toc/540631 , accessed on May 4, 2024.