Kotlyar, G. V.; Zakharov, Y. D.; Kropacheva, G. S.; Pronina, G. P.; Chediya, I. O.; Burago, V. I. (1989). ?????????????? ???? ???????? ????????????? ????: ????????? ???? ???? - Evolution of the latest Permian biota, Midian regional stage in the USSR. Nauka, Leningrad. 1-177., page(s): p. 98, pl. 2, figs. 19-24 (holotype fig. 23).