Zeithaml, V. A., & Bitner, M. J. (2003). Services marketing: Integrating customer focus across the firm (3rd ed.). McGraw-Hill/Irwin.

Zeithaml, Valarie A., and Mary Jo Bitner. Services Marketing: Integrating Customer Focus Across the Firm. 3rd ed. Boston: McGraw-Hill/Irwin, 2003.

Zeithaml, Valarie A., and Mary Jo Bitner. Services Marketing: Integrating Customer Focus Across the Firm. 3rd ed. McGraw-Hill/Irwin, 2003.