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Dyfyniad Arddull ChicagoArmstrong, Gary, Philip Kotler, and Marc O. Opresnik. Marketing: An Introduction. Thirteenth edition. Harlow, Essex, England: Pearson Education Limited, 2017.
Dyfyniad MLAArmstrong, Gary, et al. Marketing: An Introduction. Thirteenth edition. Pearson Education Limited, 2017.
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