United States. Department of the Treasury. "Surtax Rates Under Different Plans, April 21, 1924," in United States. Department of the Treasury. "Volume 3A," Press Releases of the United States Department of the Treasury (January 5, 1924 - December 7, 1925) : 95-96. https://fraser.stlouisfed.org/title/6111/item/586840/toc/558533 , accessed on May 19, 2024.