Yu. A. Mamaev, Director, Prof., Doc. Sci. (Techn.), G. V. Sekisov, Head of Laboratory, Doc. Sci. (Techn.), A. P. Van-
Van
-E, Head of Laboratory, Doc. Sci. (Geol.
Min.), V. S. Litvintsev, Deputy Director, Doc. Sci. (Techn.), Institute of Mining Engineering, Far-
Eastern Branch of the Russian Academy of Science