Gaya APA
CUNNINGHAM, W, P., CUNNINGHAM, M, A. (2008).
Environmental science : (10th ed.).
Boston:
McGraw-Hill Higner Education.
Gaya MLA
CUNNINGHAM, William, P.., CUNNINGHAM, Mary, Ann.
"Environmental science :".
10th ed.
Boston:
McGraw-Hill Higner Education,
2008.
Buku.