Federal Reserve Bank of Chicago. "June 1967," Business Conditions (Federal Reserve Bank of Chicago) (June 1967). https://fraser.stlouisfed.org/title/5562/item/540252, accessed on April 24, 2024.
Federal Reserve Bank of Chicago. "June 1967," Business Conditions (Federal Reserve Bank of Chicago) (June 1967). https://fraser.stlouisfed.org/title/5562/item/540252, accessed on April 24, 2024.