Etzel, M. J., & Walker, B. J. S. (2001). Marketing (12th ed.). McGraw-Hill.
Dyfyniad Arddull ChicagoEtzel, Michael J., and Bruce J. Stanton Walker. Marketing. 12th ed. Boston: McGraw-Hill, 2001.
Dyfyniad MLAEtzel, Michael J., and Bruce J. Stanton Walker. Marketing. 12th ed. McGraw-Hill, 2001.
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