Gaya APA
Keller, B, T.
(1952).
Introduction to GEOLOGY
(
Ed.3)
.
New York:
McGRAW-HILL BOOK COMPANY.
Gaya MLA
Keller, Branson, Tarr.
"Introduction to GEOLOGY".
Ed.3
New York:
McGRAW-HILL BOOK COMPANY,
1952.
Text.