APA aipamena

(2000).  Ecosystems around the world.  MCGraww-Hill.

Chicago Style aipamena

 Ecosystems Around the World.  MCGraww-Hill, 2000.

MLA aipamena

 Ecosystems Around the World.  MCGraww-Hill, 2000.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.