Board of Governors of the Federal Reserve System (U.S.), 1935-. "Market Groupings, Not Seasonally Adjusted," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "March 17, 1969," G.12.3 Industrial Production (1969-03-17) : 4-4. https://fraser.stlouisfed.org/title/55/item/59771/toc/465859 , accessed on April 19, 2024.