Gaya APA
Foster, D, L., Sastrio, T, B. (1991).
Sales And Marketing For The Travel Profesional (Ed. 1).
Jakarta:
PT. Rajagrafndo Persada.
Gaya MLA
Foster, Dennis, L.., Sastrio, Tri, Budhi.
"Sales And Marketing For The Travel Profesional".
Ed. 1
Jakarta:
PT. Rajagrafndo Persada,
1991.
Text.