APA-ийн эшлэл(7 дахь хэвлэлт)

Krugman, P. R., & Obstfeld, M. (1991). International economics: Theory and policy (2nd ed.). Harper Collins.

Чикаго-гийн эшлэл (17 дахь хэвлэлт)

Krugman, Paul R., ба Maurice Obstfeld. International Economics: Theory and Policy. 2nd ed. New York: Harper Collins, 1991.

MLA -ийн эшлэл (9 дэх хэвлэлт)

Krugman, Paul R., ба Maurice Obstfeld. International Economics: Theory and Policy. 2nd ed. Harper Collins, 1991.