Coughlin, Cletus C. "The Increasing Importance of Proximity for Exports from U.S. States," in Federal Reserve Bank of St. Louis. "November/December 2004, Vol. 86, No. 6," Review (Federal Reserve Bank of St. Louis) (November 2004) : 1-18. https://fraser.stlouisfed.org/title/820/item/620731/toc/633905 , accessed on April 24, 2024.