Gaya APA

Koopmans, T, C. (1957). Three Essays on the State of Economic Science . New York: McGraw-Hill Book Company, Inc. - New York.

Gaya MLA

Koopmans, Tjalling, C.. "Three Essays on the State of Economic Science". New York: McGraw-Hill Book Company, Inc. - New York, 1957. Koleksi Elektronik.