Zeithaml, V. A., Bitner, M. J., & Gremler, D. D. (2013). Services marketing: Integrating customer focus across the firm (6th ed.). গপএৎধ-িঐরষষ/ওৎরিহ.

Zeithaml, Valarie A., Mary Jo Bitner, and Dwayne D. Gremler. Services Marketing: Integrating Customer Focus Across the Firm. 6th ed. New York: গপএৎধ-িঐরষষ/ওৎরিহ, 2013.

Zeithaml, Valarie A., et al. Services Marketing: Integrating Customer Focus Across the Firm. 6th ed. গপএৎধ-িঐরষষ/ওৎরিহ, 2013.