Gaya APA

Ekelund, R, B., Herbert, R, F. (1997). A history of economic theory and method / Robert B. Ekelund (4th ed). New York: The McGraw-Hill Companies.

Gaya MLA

Ekelund, Robert, B.., Herbert, Robert, F.. "A history of economic theory and method / Robert B. Ekelund". 4th ed New York: The McGraw-Hill Companies, 1997. Buku.