Shumenko, S. I.; Ushakova, M. G. (1980): Izvestkovyye nanofossilii v kernakh glubokovodnogo bureniya Calcareous nannofossils in cores from deep-sea drilling. Izd. Nauka, Moscow, USSR, In: Neprochnov, Yu. P. (editor), Geologicheskaya istoriya Chernogo morya po rezul'tatam glubokovodnogo bureniya The geologic history of the Black Sea from the results of deep-sea drilling, 71-73, georefid:1982-002976