Gaya APA
Energy, M, O, M, A. (1985).
Ombilin Ii Coal Development And Trasportation Project .
Bandung:
Pusat Sumber Daya Geologi.
Gaya MLA
Energy, Ministry, Of, Mines, And.
"Ombilin Ii Coal Development And Trasportation Project".
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Pusat Sumber Daya Geologi,
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Batubara.