Voith, Richard. "Unequal Subsidies in Highway Investment : What Are the Consequences?," in Federal Reserve Bank of Philadelphia. "November/December 1989," Business Review (Federal Reserve Bank of Philadelphia) (November/December 1989) : 9-18. https://fraser.stlouisfed.org/title/5580/item/557649/toc/523697 , accessed on May 1, 2024.