Gaya APA
Environmental science a global concern. (2007).
Boston:
Mc Graw Hill.
Gaya Chicago
Environmental science a global concern.
.
Boston:
Mc Graw Hill,
2007.
Buku.
Gaya MLA
Environmental science a global concern.
.
Boston:
Mc Graw Hill,
2007.
Buku.
Gaya Turabian
Environmental science a global concern.
Boston:
Mc Graw Hill,
2007.
Buku.