Gaya APA
RIZKA, N., N., H., &., H. (2015).
IELTS PREPARATION: LETS GET THE HIGHEST SCORE FOR IELTS .
Yogyakarta:
PUSTAKA BARU PRESS.
Gaya MLA
RIZKA, NISWATIN, NURUL, HIDAYATI, &, HAIRA.
"IELTS PREPARATION: LETS GET THE HIGHEST SCORE FOR IELTS".
Yogyakarta:
PUSTAKA BARU PRESS,
2015.
Buku Inti.