Van Tol, A. (2010). Orca echoes resource guide. Orca Book Publishers.
Dyfyniad Arddull ChicagoVan Tol, Alex. Orca Echoes Resource Guide. [Victoria, British Columbia]: Orca Book Publishers, 2010.
Dyfyniad MLAVan Tol, Alex. Orca Echoes Resource Guide. Orca Book Publishers, 2010.
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