APA (7th ed.) Zitazioa

Kearl, J. (1993). Principles of Economics. D.C.Heath and Co..

Chicago Style (17th ed.) Zitazioa

Kearl, James. Principles of Economics. Massachusetts: D.C.Heath and Co., 1993.

MLA (9th ed.) Zitazioa

Kearl, James. Principles of Economics. D.C.Heath and Co., 1993.