Gaya APA

Djunuddin, A. et al (1984). 1984 Index of Northern Sumatra Geological and Geochemical Maps, and Nothern Sumatra Bibliography . Bandung: Pusat Sumber Daya Geologi.

Gaya MLA

Djunuddin, A.. et al. "1984 Index of Northern Sumatra Geological and Geochemical Maps, and Nothern Sumatra Bibliography". Bandung: Pusat Sumber Daya Geologi, 1984. Geokimia.