Nessov, L.A. & Udovichenko, N.I. (1984)
Paleogene sea snakes and elasmobranch fishes of South Kazakhstan. Paleontologitchesky Sbornik, 21, 69–74

Guinot, G. & Condamine, F.L. (2023)
Global impact and selectivity of the Cretaceous-Paleogene mass extinction among sharks, skates, and rays. Science, 379, 802–806
DOI: 10.1126/science.abn2080