United States. Department of the Treasury. "IET extension with letters attached, January 22, 1973," in United States. Department of the Treasury. "Volume 182," Press Releases of the United States Department of the Treasury (January 2, 1973 - February 28, 1973) : 144-147. https://fraser.stlouisfed.org/title/6111/item/587025/toc/542922 , accessed on June 25, 2024.