Borys Borowka. IMPACT OF GEOLOGICAL AND MINING CONDITIONS ON TO COSTS OF DRILLING THE ACCESS WORKINGS IN HARD COAL MINES WITHIN THE UPPER SILESIAN COAL BASIN (POLAND). SGEM International Multidisciplinary Scientific GeoConference EXPO Proceedings; 15th International Multidisciplinary Scientific GeoConference SGEM2015, SCIENCE AND TECHNOLOGIES IN GEOLOGY, EXPLORATION AND MINING, 2015. https://doi.org/10.5593/sgem2015/b11/s1.030