Gaya APA

simanjuntak, H., geologist, G, E. (1993). Sapphire Occurrences In Upper Barito Central Kalimantan . Bandung: John Wiley & Sons. Inc.

Gaya MLA

simanjuntak, H.r.w., geologist, Gem's, Exploration. "Sapphire Occurrences In Upper Barito Central Kalimantan". Bandung: John Wiley & Sons. Inc, 1993. Bukan Logam.