Gaya APA

Drs.Johannas, . (1985). Ombilin II Coal Mine Development And Transportation Project Dilling Program Addendum . Bandung: Pusat Sumber Daya Geologi.

Gaya MLA

Drs.Johannas, . "Ombilin II Coal Mine Development And Transportation Project Dilling Program Addendum". Bandung: Pusat Sumber Daya Geologi, 1985. Batubara.