Federal Reserve Bank of Chicago. "September 1966," Business Conditions (Federal Reserve Bank of Chicago) (September 1966). https://fraser.stlouisfed.org/title/5562/item/540243, accessed on April 24, 2024.
Federal Reserve Bank of Chicago. "September 1966," Business Conditions (Federal Reserve Bank of Chicago) (September 1966). https://fraser.stlouisfed.org/title/5562/item/540243, accessed on April 24, 2024.