Kh. E. Sharafeldin Russian State University of Geological Exploration named after Sergo Ordzhonikidze, 23 Miklukho-Maklay Str., Moscow 117485, Russia Russian Federation
A. A. Vercheba Russian State University of Geological Exploration named after Sergo Ordzhonikidze, 23 Miklukho-Maklay Str., Moscow 117485, Russia Russian Federation
Dr.geol.-min.Sci., Prof. Dean of Geological Exploration Faculty