APA引文

Krugman, P. R. (1994). International economics: Theory and policy. New York: HarperCollins College Publishers.

Trích dẫn kiểu Chicago

Krugman, Paul R. International Economics: Theory and Policy. New York: HarperCollins College Publishers, 1994.

MLA引文

Krugman, Paul R. International Economics: Theory and Policy. New York: HarperCollins College Publishers, 1994.

警告：這些引文格式不一定是100％准確.