Dyfyniad APA

Sviokla, J. J., & Shapiro, B. P. (1993). Keeping customers (11th ed.). HBR.

Dyfyniad Arddull Chicago

Sviokla, John J., and Benson P. Shapiro. Keeping Customers. 11th ed. HBR, 1993.

Dyfyniad MLA

Sviokla, John J., and Benson P. Shapiro. Keeping Customers. 11th ed. HBR, 1993.

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