United States. Department of the Treasury. "Income and Profits Taxes Due June 15, 1919, May 7, 1919," in United States. Department of the Treasury. "Volume 1A," Press Releases of the United States Department of the Treasury (March 30, 1918 - December 26, 1921) : 47-50. https://fraser.stlouisfed.org/title/6111/item/586836/toc/557979 , accessed on September 22, 2023.