United States. Department of the Treasury. "Lead and Zinc, October 12, 1962, Release Number d-637," in United States. Department of the Treasury. "Volume 134," Press Releases of the United States Department of the Treasury (October 2, 1962 - December 29, 1962) : 101-104. https://fraser.stlouisfed.org/title/6111/item/586977/toc/538955 , accessed on June 24, 2024.