APA (7th ed.) Zitazioa

HALM, G. N. (1968). Economic systems: A comparative analysis. Holt.

Chicago Style (17th ed.) Zitazioa

HALM, George N. Economic Systems: A Comparative Analysis. New York: Holt, 1968.

MLA (9th ed.) Zitazioa

HALM, George N. Economic Systems: A Comparative Analysis. Holt, 1968.