Gaya APA
Spencer, Edgar W.. (1983).
Physical geology .
Reading:
Addison-Wesley.
Gaya Chicago
Spencer, Edgar W..
Physical geology.
Reading:
Addison-Wesley,
1983.
Text.
Gaya MLA
Spencer, Edgar W..
Physical geology.
Reading:
Addison-Wesley,
1983.
Text.
Gaya Turabian
Spencer, Edgar W..
Physical geology.
Reading:
Addison-Wesley,
1983.
Print.