B. Wielstra, S. N. Litvinchuk, B. Naumov, N. Tzankov, and J. W. Arntzen, “A revised taxonomy of crested newts in the Triturus karelinii group (Amphibia: Caudata: Salamandridae), with the description of a new species”, Zootaxa, vol. 3682, no. 3, pp. 441–453, Jun. 2013.