Gaya APA
Geologi, P, S, D. (1986).
Ombilin II Coal Mine Development And Transportation Project Geological Report, V TO IX .
Bandung:
Pusat Sumber Daya Geologi.
Gaya MLA
Geologi, Pusat, Sumber, Daya.
"Ombilin II Coal Mine Development And Transportation Project Geological Report, V TO IX".
Bandung:
Pusat Sumber Daya Geologi,
1986.
Encyclopaedia.