Campbell, J. A. (1988). The distribucion, variation, natural history, and relationships of Porthidium barbouri (Viperidae). Instituto de Ecología, A.C.
Chicago-viite (17. p.)Campbell, Jonathan A. The Distribucion, Variation, Natural History, and Relationships of Porthidium Barbouri (Viperidae). Instituto de Ecología, A.C, 1988.
MLA-viite (9. p.)Campbell, Jonathan A. The Distribucion, Variation, Natural History, and Relationships of Porthidium Barbouri (Viperidae). Instituto de Ecología, A.C, 1988.
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