Jochen Wirtz. (2019). Service Marketing (8th ed.). pearson.
Lua i Stíl Chicago (17ú heag.)Jochen Wirtz. Service Marketing. 8th ed. Delhi: pearson, 2019.
Lua MLA (9ú heag.)Jochen Wirtz. Service Marketing. 8th ed. pearson, 2019.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.