Gaya APA

Krugman, P, R., Obsfeld, M. (2003). International Economics: Theory and Policy (Edisi 6). United States of America: Person Eduation Inc. , Right and Contract Departement.

Gaya MLA

Krugman, Paul, R.., Obsfeld, Maurice. "International Economics: Theory and Policy". Edisi 6 United States of America: Person Eduation Inc. , Right and Contract Departement, 2003. Text.