Gaya APA
Gibson, C. et al (1999).
IELTS practice now : Practice in Listening, Reading, Writing and Speaking for the IELTS Test .
Australia:
Calusa.
Gaya MLA
Gibson, Carol. et al.
"IELTS practice now : Practice in Listening, Reading, Writing and Speaking for the IELTS Test".
Australia:
Calusa,
1999.
Text.