Gaya APA
Heo, S., Choi, Y.
(2010).
Why : Environment - Lingkungan
.
Jakarta:
Elex Media Komputindo.
Gaya MLA
Heo, Soon-Boon., Choi, Yeol.
"Why : Environment - Lingkungan".
Jakarta:
Elex Media Komputindo,
2010.
Text.