Wirtz, J. Services Marketing: People, Technology, Strategy (9th.). World Scientific.
Čikaški stil citiranja (17. izdanje)Wirtz, Jochen. Services Marketing: People, Technology, Strategy. 9th. World Scientific.
MLA način citiranja (9. izdanje)Wirtz, Jochen. Services Marketing: People, Technology, Strategy. 9th. World Scientific.
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