Gaya APA
ZEITHAML, V, A. (1990).
DELIVERING QUALITY SERVICE: Balancing Customer Perceptions and Expectations .
California:
THE FREE PRESS.
Gaya MLA
ZEITHAML, VALARIE, A.
"DELIVERING QUALITY SERVICE: Balancing Customer Perceptions and Expectations".
California:
THE FREE PRESS,
1990.
Text.