Free Improving Safety when Extracting Water-soluble Ores by Optimizing the Parameters of the Backfill Mass Khayrutdinov M.M., Kongar-Syuryun Ch.B., Khayrutdinov A.M., Tyulyaeva Yu.S. DOI: 10.24000/0409-2961-2021-1-53-59 Year: 2021 Issue num: 1 more