Federal Reserve Bank of Chicago. "March 1961," Business Conditions (Federal Reserve Bank of Chicago) (March 1961). https://fraser.stlouisfed.org/title/5562/item/540177, accessed on April 18, 2024.
Federal Reserve Bank of Chicago. "March 1961," Business Conditions (Federal Reserve Bank of Chicago) (March 1961). https://fraser.stlouisfed.org/title/5562/item/540177, accessed on April 18, 2024.