APA ציטוט

 Krugman, P. R. (2015).  International economics: Theory and policy.  Pearson.

Trích dẫn kiểu Chicago

 Krugman, Paul R.  International Economics: Theory and Policy.  Pearson, 2015.

ציטוט MLA

 Krugman, Paul R.  International Economics: Theory and Policy.  Pearson, 2015.