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Friesen, V.L.; Anderson, D.J.; Steeves, T.E.; Jones, H. & Schreiber, E.A. (2002): Molecular Support for Species Status of the Nazca Booby (Sula granti). Auk119(3): 820–826. [English with Spanish abstract] DOI: 10.1642/0004-8038(2002)119[0820:MSFSSO]2.0.CO;2 PDF fulltextDiarsipkan 2016-03-03 di Wayback Machine.
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Friesen, V.L.; Anderson, D.J.; Steeves, T.E.; Jones, H. & Schreiber, E.A. (2002): Molecular Support for Species Status of the Nazca Booby (Sula granti). Auk119(3): 820–826. [English with Spanish abstract] DOI: 10.1642/0004-8038(2002)119[0820:MSFSSO]2.0.CO;2 PDF fulltextDiarsipkan 2016-03-03 di Wayback Machine.