Gaya APA
BARBER, A, C, M, M, J. (2005).
Sumatra: Geology, Resources and Tectonic Evolution .
:
Geological Society.
Gaya MLA
BARBER, A.J.;, CROW,, M.J.;, MILSOM,, J.S..
"Sumatra: Geology, Resources and Tectonic Evolution".
:
Geological Society,
2005.
Buku.