@ARTICLE{Drzewiecki_Jan_Dependence_2001,
 author={Drzewiecki, Jan},
 number={No 1},
 journal={Archives of Mining Sciences},
 pages={3-17},
 howpublished={online},
 year={2001},
 publisher={Committee of Mining PAS},
 type={Article},
 title={Dependence of Active Volume of the Rock Mass on the Advance Rate of Longwall Coalface},
 URL={http://journals.pan.pl/Content/132203/PDF/3_MINING_46_1_2001_Drzewiecki_DEPENDENCE.pdf},
}