Gaya APA
Legget, R, F., Hatheway, A, W. (1988).
Geology and Engineering, 3rd Edition .
New York:
McGraw-Hill Book Company.
Gaya MLA
Legget, Robert, F.., Hatheway, Allen, W..
"Geology and Engineering, 3rd Edition".
New York:
McGraw-Hill Book Company,
1988.
Text.