Não informado. (2007). Report of the Penrose Research Laboratory. Zoological Society of Philadelphia.
Chicago-viite (17. p.)Não informado. Report of the Penrose Research Laboratory. Philadelphia, Pa: Zoological Society of Philadelphia, 2007.
MLA-viite (8. p.)Não informado. Report of the Penrose Research Laboratory. Zoological Society of Philadelphia, 2007.
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