Armentrout, Claire and Luttrell, Clifton B. "Economic Activity Slows in the Central Mississippi Valley in 1967," in Federal Reserve Bank of St. Louis. "January 1968," Review (Federal Reserve Bank of St. Louis) (January 1968) : 5-16. https://fraser.stlouisfed.org/title/820/item/24410/toc/499543 , accessed on April 25, 2024.