David C. Blackburn; David B. Wake (23 Dec 2011). "Class Amphibia Gray, 1825"(PDF). Animal Biodiversity: An Outline of Higher-level Classification and Survey of Taxonomic Richness (بالإنجليزية). 3148 (1): 39–55. ISBN:978-1-86977-849-1. QID:Q19978589.
David C. Blackburn; David B. Wake (23 Dec 2011). "Class Amphibia Gray, 1825"(PDF). Animal Biodiversity: An Outline of Higher-level Classification and Survey of Taxonomic Richness (بالإنجليزية). 3148 (1): 39–55. ISBN:978-1-86977-849-1. QID:Q19978589.