United States. Department of the Treasury. "Coffee, July 18, 1967," in United States. Department of the Treasury. "Volume 158," Press Releases of the United States Department of the Treasury (June 1, 1967 - August 29, 1967) : 333-344. https://fraser.stlouisfed.org/title/6111/item/587001/toc/540764 , accessed on May 19, 2024.