Federal Reserve Bank of Chicago. "April 1969," Business Conditions (Federal Reserve Bank of Chicago) (April 1969). https://fraser.stlouisfed.org/title/5562/item/540274, accessed on April 17, 2024.
Federal Reserve Bank of Chicago. "April 1969," Business Conditions (Federal Reserve Bank of Chicago) (April 1969). https://fraser.stlouisfed.org/title/5562/item/540274, accessed on April 17, 2024.