APA (7th ed.) Citation

Krugman, P. R., & Obstfeld, M. (2009). International Economics: Theory and policy (7th ed.). Addison-Wesley.

Chicago Style (17th ed.) Citation

Krugman, Paul R., and Maurice Obstfeld. International Economics: Theory and Policy. 7th ed. Boston: Addison-Wesley, 2009.

MLA (8th ed.) Citation

Krugman, Paul R., and Maurice Obstfeld. International Economics: Theory and Policy. 7th ed. Addison-Wesley, 2009.