Gaya APA
CHA, D, A, B, S. (2008).
Hotel Courtesy : The Secret Of 5 Star Hotel Courtesy .
Yogyakarta:
CV. Andi Offset.
Gaya MLA
CHA, Drs., A., Bambang, Sujatno,.
"Hotel Courtesy : The Secret Of 5 Star Hotel Courtesy".
Yogyakarta:
CV. Andi Offset,
2008.
Text.