APA-viite

Krugman, P. R. (2004). International economics: Theory and policy (6th ed.). Pearson Education.

Chicago-tyylinen lähdeviittaus

Krugman, Paul R. International Economics: Theory and Policy. 6th ed. Delhi: Pearson Education, 2004.

MLA-viite

Krugman, Paul R. International Economics: Theory and Policy. 6th ed. Pearson Education, 2004.