Carrasco, P. A., M. B. Harvey, and A. M. Saravia. “The Rare Andean Pitviper Rhinocerophis Jonathani (Serpentes: Viperidae: Crotalinae): Redescription With Comments on Its Systematics and Biogeography”. Zootaxa, vol. 2283, no. 1, Nov. 2009, pp. 1–15, doi:10.11646/zootaxa.2283.1.1.