Gaya APA
Enterprices, D, O, M, A, C. (2004).
Indonesia minerals & coal statistics 2004 .
:
Dit. Pengusahaan Batubara.
Gaya MLA
Enterprices, DIRECTORATE, Of, Mineral, And, Coal.
"Indonesia minerals & coal statistics 2004".
:
Dit. Pengusahaan Batubara,
2004.
Laporan.