APA

krugman p. R., . (2018). International Economics. ENGLAND: PEARSON.

Chicago

krugman paul R, . 2018. International Economics. ENGLAND: PEARSON.

Harvard

krugman p. R., . (2018). International Economics. ENGLAND: PEARSON.

MLA

krugman paul R, . International Economics. ENGLAND: PEARSON. 2018.