Federal Reserve Bank of Chicago. "Optional Redemption of Certificates of Indebtedness Series "B" 1920, Dated August 15, 1919, Maturing January 15, 1920, Circular no. 226" in Federal Reserve Bank of Chicago Bulletins and Circular Letters (December 31, 1919). https://fraser.stlouisfed.org/title/7180/item/655640, accessed on November 23, 2024.