Board of Governors of the Federal Reserve System (U.S.). Division of Research and Statistics and Knapp, J. Burke, 1913-2009. Letter to Charles P. Kindleberger, Box 37, Folder 15, Item 4, Marriner S. Eccles Papers. https://fraser.stlouisfed.org/archival/1343/item/467988, accessed on March 18, 2025.