APA-referens (7:e uppl.)

Koopmans, T. C. (1957). Three essays on the state of economic science (Paperback edition.). McGraw-Hill.

Chicago-referens (17:e uppl.)

Koopmans, Tjalling C. Three Essays on the State of Economic Science. Paperback edition. New York: McGraw-Hill, 1957.

MLA-referens (8:e uppl.)

Koopmans, Tjalling C. Three Essays on the State of Economic Science. Paperback edition. McGraw-Hill, 1957.