@ARTICLE{Nowak_Jacek_Changes_2017, author={Nowak, Jacek and Kokowska-Pawłowska, Magdalena}, number={No 3}, journal={Archives of Mining Sciences}, howpublished={online}, year={2017}, publisher={Committee of Mining PAS}, title={Changes in the Concentration of Some Rare Earth Elements in Coal Waste}, URL={http://journals.pan.pl/Content/105591/PDF/10267-Volume62_Issue3-05_paper.pdf}, doi={10.1515/amsc-2017-0037}, }