Balisco, R. A. T. (2015). Notes on the Gracious Sea Urchin Tripneustes gratilla (Echinodermata: Echinoidea) in Pag-asa Island, Kalayaan, Palawan, Philippines. The Palawan Scientist.
Chicago-viite (17. p.)Balisco, Rodulf Anthony T. "Notes on the Gracious Sea Urchin Tripneustes Gratilla (Echinodermata: Echinoidea) in Pag-asa Island, Kalayaan, Palawan, Philippines." The Palawan Scientist 2015.
MLA-viite (9. p.)Balisco, Rodulf Anthony T. "Notes on the Gracious Sea Urchin Tripneustes Gratilla (Echinodermata: Echinoidea) in Pag-asa Island, Kalayaan, Palawan, Philippines." The Palawan Scientist, 2015.
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