Klimenko, Y. V., & Dorotyak, Y. B. (2017). Microfossils distribution in the callovian sediments of the north-western part of Dnieper-Donets depression. Visnyk of V. N. Karazin Kharkiv National University, Series "Geology. Geography. Ecology", (45), 43-52. Retrieved from https://periodicals.karazin.ua/geoeco/article/view/8180