@ARTICLE{Szlązak_Nikodem_The_2016, author={Szlązak, Nikodem and Swolkień, Justyna}, number={No 3}, journal={Archives of Mining Sciences}, howpublished={online}, year={2016}, publisher={Committee of Mining PAS}, title={The Effectiveness of the Methane Drainage of Rock-Mass with a U Ventilation System}, URL={http://journals.pan.pl/Content/105536/PDF/10267-Volume61_Issue3-12_paper.pdf}, doi={10.1515/amsc-2016-0044}, }