Gaya APA
SIMATUPANG, M., Wahyu, B, N. (1994).
Enviromental Aspects of Mining in Indonesia .
Jakarta:
Indonesian Mining Association.
Gaya MLA
SIMATUPANG, MARANGIN., Wahyu, Beni, N.
"Enviromental Aspects of Mining in Indonesia".
Jakarta:
Indonesian Mining Association,
1994.
Text.