Frost, Darrel R. (2019). "Callulops kopsteini (Mertens, 1930)". Amphibian Species of the World: an Online Reference. Version 6.0. American Museum of Natural History. Retrieved 25 June 2019.
books.google.com
Lonely Planet; Ryan Ver Berkmoes; Celeste Brash; Muhammad Cohen; Mark Elliott; Guyan Mitra; John Noble; Adam Skolnick; Iain Stewart; Steve Waters (2010). Lonely Planet Indonesia. Lonely Planet Publications. p. 741. ISBN978-1-74104-830-8.