Gaya APA
Foster, D, L. (1993).
Sales and marketing for the travel professional (International Editions).
Illinois:
Glencoe-Macmillan/McGraw-Hill.
Gaya MLA
Foster, Dennis, L..
"Sales and marketing for the travel professional".
International Editions
Illinois:
Glencoe-Macmillan/McGraw-Hill,
1993.
BUKU.