Relationship between the Power of the Two-Bit Cutting Body Rotation Drive of the Roadheader and Hardness of Broken RockAlexey Khoreshok, Leonid Mametiev, Alexander Tsekhin and Andrey BorisovE3S Web Conf., 41 (2018) 03017DOI: https://doi.org/10.1051/e3sconf/20184103017