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Linda R. Maxson, Immunological Evidence Pertaining to Relationships between Old World Hyla arborea (Amphibia, Anura, Hylidae) and North American Hyla, Journal of Herpetology, Vol. 12, No. 1 (Feb. 27, 1978), pp. 98-100
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Linda R. Maxson (1978) studied this question.
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