United States. Department of the Treasury. "May 1973 Residual Oil Prices mixed, July 20, 1973," in United States. Department of the Treasury. "Volume 185," Press Releases of the United States Department of the Treasury (July 2, 1973 - August 31, 1973) : 248-253. https://fraser.stlouisfed.org/title/6111/item/587028/toc/543333 , accessed on July 10, 2024.