Lamar, William W., and Mahmood Sasa. “A New Species of Hognose Pitviper, Genus <i>Porthidium</i≫, from the Southwestern Pacific of Costa Rica (Serpentes: Viperidae)”. Revista de Biología Tropical 51, no. 3-4 (December 1, 2003): 797–804. Accessed November 25, 2024. https://revistas.ucr.ac.cr/index.php/rbt/article/view/16051.