Gaya APA
Helvarg, D. (2005).
The Ocean and coastal conservation guide : the blue movement directory 2005-2006 / editor: David Helvarg .
Washinto:
Island Press.
Gaya MLA
Helvarg, David..
"The Ocean and coastal conservation guide : the blue movement directory 2005-2006 / editor: David Helvarg".
Washinto:
Island Press,
2005.
Buku.