Gaya APA

Reference, T, O. (1993). The Republic Of Indonesia Ministry Of Mines And Eergy Directorate General Of Mines Directorate Of Coal Nations Coal Policy Study . Jakarta: Pusat Sumber Daya Geologi.

Gaya MLA

Reference, Terms, Of. "The Republic Of Indonesia Ministry Of Mines And Eergy Directorate General Of Mines Directorate Of Coal Nations Coal Policy Study". Jakarta: Pusat Sumber Daya Geologi, 1993. Batubara.