Não informado. (2008). State University of Iowa studies in natural history. State University of Iowa.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. State University of Iowa Studies in Natural History. Iowa City, Iowa: State University of Iowa, 2008.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. State University of Iowa Studies in Natural History. State University of Iowa, 2008.
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