Federal Reserve Bank of Chicago. "February 1969," Business Conditions (Federal Reserve Bank of Chicago) (February 1969). https://fraser.stlouisfed.org/title/5562/item/540272, accessed on May 1, 2024.
Federal Reserve Bank of Chicago. "February 1969," Business Conditions (Federal Reserve Bank of Chicago) (February 1969). https://fraser.stlouisfed.org/title/5562/item/540272, accessed on May 1, 2024.