^"Hallowell". The Reptile Database. www.reptile-database.org.
^Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. (ردمك 978-1-4214-0135-5). ("Hallowell", p. 114).
^Beolens, Bo; Watkins, Michael; Grayson, Michael (2013). The Eponym Dictionary of Amphibians. Exeter, England: Pelagic Publishing Ltd. (Kindle edition).
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