Ritzmann , Karin. 2006. Записки Горного института 167 (2), 71-76. https://pmi.spmi.ru/pmi/article/view/7962.

Ritzmann , Karin. 2006. "Marine/continental Facies Patterns, Sequence Stratigraphy and a Gocad-3D-Modelling of the carboniferous/Permian-Boundary of the Donetsk Basin". Journal of Mining Institute 167 (2), 71-76. https://pmi.spmi.ru/pmi/article/view/7962.