United States. Department of the Treasury. "Old-age Pension Tax Study, December 1, 1947," in United States. Department of the Treasury. "Volume 70," Press Releases of the United States Department of the Treasury (November 21, 1947 - December 30, 1947) : 95-145. https://fraser.stlouisfed.org/title/6111/item/586913/toc/564510 , accessed on April 19, 2024.