Gaya APA
RIYANTO, S.
(2004).
Gateway english for active communication / Slamet Riyanto
.
:
Pustaka Pelajar.
Gaya MLA
RIYANTO, Slamet.
"Gateway english for active communication / Slamet Riyanto".
:
Pustaka Pelajar,
2004.
Referensi.