Gaya APA

Zeithaml, V, A. et al (2009). Services marketing : integrating customer focus across the firm ( 5th.Ed.). New York: McGraw-Hill.

Gaya MLA

Zeithaml, Valarie, A.. et al. " Services marketing : integrating customer focus across the firm". 5th.Ed. New York: McGraw-Hill, 2009. BUKU.