APA (7th ed.) Zitazioa
Hardwick, P., & Langmead, J. a. K. B. (1999). An introduction to modern economics (5th ed.). Prentice hall.
Chicago Style (17th ed.) Zitazioa
Hardwick, Philip, eta John and Khan Bhadur Langmead. An Introduction to Modern Economics. 5th ed. Harlow, England: Prentice hall, 1999.
MLA (9th ed.) Zitazioa
Hardwick, Philip, eta John and Khan Bhadur Langmead. An Introduction to Modern Economics. 5th ed. Prentice hall, 1999.
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