Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "Industrial Production - Indexes and Gross Value," in Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "June 1989," Federal Reserve Bulletin (June 1989) : 87-88. https://fraser.stlouisfed.org/title/62/item/20805/toc/160470 , accessed on May 6, 2024.