Gaya APA
AHRENS, L.
(1961).
PHYSICSB AND CHEMISTRY OF THE EARTH
.
London:
Pusat Sumber Daya Geologi.
Gaya MLA
AHRENS, L.H.
"PHYSICSB AND CHEMISTRY OF THE EARTH".
London:
Pusat Sumber Daya Geologi,
1961.
Textbook.