Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "Index Numbers of Wholesale Prices," in Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "May 1921," Federal Reserve Bulletin (May 1921) : 103-103. https://fraser.stlouisfed.org/title/62/item/20523/toc/260769 , accessed on April 23, 2024.