Gaya APA
Djumarna, U., S., K. (1969).
Limestone deposits in Riau daratan Djambi northern part of South Sumatra, central & souteast Kalimantan and the southern part of west Irian. .
Bandung:
Pusat Sumber Daya Geologi.
Gaya MLA
Djumarna, U.., S., Kadar.
"Limestone deposits in Riau daratan Djambi northern part of South Sumatra, central & souteast Kalimantan and the southern part of west Irian.".
Bandung:
Pusat Sumber Daya Geologi,
1969.
Bukan Logam.