Gaya APA

SITUMORANG, B., Sulistiyani, A, T. (1989). Proceedings: Sixth regional conference on the geology, mineral and hydrocarbon resource of southeast Asia . : IAGI.

Gaya MLA

SITUMORANG, B.., Sulistiyani, Ambar, Teguh.. "Proceedings: Sixth regional conference on the geology, mineral and hydrocarbon resource of southeast Asia". : IAGI, 1989. Buku.