ZEITHAML VALARIE A. (1990). DELIVERING QUALITY SERVICE: BALANCING CUSTOMER PERCEPTIONS AND EXPECTIONS. FREE PRESS.
Chicago-čujuhus (17. p.)ZEITHAML VALARIE A. DELIVERING QUALITY SERVICE: BALANCING CUSTOMER PERCEPTIONS AND EXPECTIONS. NEW YORK: FREE PRESS, 1990.
MLA-čujuhus (9. p.)ZEITHAML VALARIE A. DELIVERING QUALITY SERVICE: BALANCING CUSTOMER PERCEPTIONS AND EXPECTIONS. FREE PRESS, 1990.
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