United States. Department of the Treasury. "Bill Tender, April 19, 1938," in United States. Department of the Treasury. "Volume 23," Press Releases of the United States Department of the Treasury (April 16, 1938 - July 14, 1938) : 7-9. https://fraser.stlouisfed.org/title/6111/item/586864/toc/567205 , accessed on April 19, 2024.