APA (7th ed.) Zitazioa
Amacher, R. C., & Ulbrich, H. H. (1995). Economic principles & policy (6th ed.). South-Western College.
Chicago Style (17th ed.) Zitazioa
Amacher, Ryan C., eta Holley H. Ulbrich. Economic Principles & Policy. 6th ed. Cincinnati: South-Western College, 1995.
MLA (9th ed.) Zitazioa
Amacher, Ryan C., eta Holley H. Ulbrich. Economic Principles & Policy. 6th ed. South-Western College, 1995.
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