Gaya APA
O'Keeffe, I, D, &, M. (2004).
English for international tourism (Third Impression).
Spain:
Pearson Longman.
Gaya MLA
O'Keeffe, Iwonna, Dubicka, &, Margaret.
"English for international tourism".
Third Impression
Spain:
Pearson Longman,
2004.
Electronic Resource.