Gaya APA
LEGGET, R, F., Boswell, P.
(1939).
Geology and Engineering
.
New York, USA:
McGraw-Hill Book Company.
Gaya MLA
LEGGET, ROBERT, F.., Boswell, P.G.H..
"Geology and Engineering".
New York, USA:
McGraw-Hill Book Company,
1939.
Text.