APA (7th ed.) Citation

Evenett, S. J., & Keller, W. (1998). On theories explaining the success of the gravity equation. National Bureau of Economic Research.

Chicago Style (17th ed.) Citation

Evenett, Simon J., and Wolfgang Keller. On Theories Explaining the Success of the Gravity Equation. Cambridge: National Bureau of Economic Research, 1998.

MLA (9th ed.) Citation

Evenett, Simon J., and Wolfgang Keller. On Theories Explaining the Success of the Gravity Equation. National Bureau of Economic Research, 1998.