Gaya APA
Curningham, W, P., Cunningham, M, A. (2013).
Principles of Environment Science : Inquiry and Application (Seventh Edition).
New York. USA:
Mc Graw Hill Education.
Gaya MLA
Curningham, William, P.., Cunningham, Mary, Ann.
"Principles of Environment Science : Inquiry and Application".
Seventh Edition
New York. USA:
Mc Graw Hill Education,
2013.
Text.