МатвєєвA. В., А. Д. Шоміна, І. В. Колосова, and В. В. Синєгубка. “Micropaleontological Characteristics of the Campanian-Maastrichtian Sediments in the Oskol River Basin”. Visnyk of V. N. Karazin Kharkiv National University, Series "Geology. Geography. Ecology", no. 44, Dec. 2016, pp. 35-44, https://periodicals.karazin.ua/geoeco/article/view/7490.