Gaya APA
Maria, M., Sudiyarto, O, H.
(2007).
4 Friends
(
1)
.
Yogyakarta:
Sheila.
Gaya MLA
Maria, Metty., Sudiyarto, Oktaviani, Hastu.
"4 Friends".
1
Yogyakarta:
Sheila,
2007.
Book.