Federal Reserve Bank of Philadelphia. "March 1968," Business Review (Federal Reserve Bank of Philadelphia) (March 1968). https://fraser.stlouisfed.org/title/5580/item/557474, accessed on April 23, 2024.
Federal Reserve Bank of Philadelphia. "March 1968," Business Review (Federal Reserve Bank of Philadelphia) (March 1968). https://fraser.stlouisfed.org/title/5580/item/557474, accessed on April 23, 2024.