United States. Department of the Treasury. "Testimony of Secretary of the Treasury Janet L. Yellen to the Subcommittee on Financial Services and General Government Committee on Appropriations, U.S. House of Representatives," Press Releases of the United States Department of the Treasury (May 27, 2021). https://fraser.stlouisfed.org/title/6111/item/603213, accessed on October 13, 2024.