United States. Department of the Treasury. "Bill Tender, December 11, 1956," in United States. Department of the Treasury. "Volume 108," Press Releases of the United States Department of the Treasury (September 1, 1956 - December 29, 1956) : 309-318. https://fraser.stlouisfed.org/title/6111/item/586951/toc/537248 , accessed on June 25, 2024.