APA (7th ed.) Zitazioa
Helvarg, D. (2005). The Ocean and Costal Conservation Guide: The Blue Movement Directory. OISLAND PRESS.
Chicago Style (17th ed.) Zitazioa
Helvarg, David. The Ocean and Costal Conservation Guide: The Blue Movement Directory. Washington DC: OISLAND PRESS, 2005.
MLA (9th ed.) Zitazioa
Helvarg, David. The Ocean and Costal Conservation Guide: The Blue Movement Directory. OISLAND PRESS, 2005.
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