Gaya APA
Enger, E, D., Smith, B, F. (2006).
Environmental science (Tenth edition).
:
The McGraw-Hill.New York.
Gaya MLA
Enger, Eldon, D., Smith, Bradley, F.
"Environmental science ".
Tenth edition
:
The McGraw-Hill.New York,
2006.
Skripsi, Tesis, Disertasi.