Increasing oil shale quality for meeting EU environmental requirementsValgma, Ingo; Karu, Veiko; Anepaio, Ain; Väizene, VivikaMining and the Environment 2007 : 8th till 10th November 2007 : Baia Mare, Romania2007 / p. 195-205 : ill Low depth mining in Estonian oil shale depositValgma, Ingo; Kattel, TõnisKolloqium : Schacht, Strecke und Tunnel2005 / p. 213-223 Multi criterial modelling of oil shale mining fields : [poster]Karu, Veiko; Västrik, Aire; Valgma, IngoMining and the Environment 2007 : 8th till 10th November 2007 : Baia Mare, Romania2007 / p. 225 : ill SSBDDs : advantageous model and efficient algorithms for digital circuit modeling, simulation & testJutman, Artur; Raik, Jaan; Ubar, Raimund-Johannes5th International Workshop on Boolean Problems : September 19-20, 2002, Freiberg (Sachsen) : proceedings2002 / p. 157-166 : ill Teilchenkinematik in Zerkleinerungs- und KlassiermaschinenKleis, Ilmar; Pappel, Toivo; Frishman, FeliksXLVI. Berg- und Hüttenmännischer Tag vom 14. bis 17. Juni 1995 : abstracts1995 / S. 149: Ill Underground mining challenges for Estonian oil shale depositValgma, Ingo; Tammeoja, Tauno; Anepaio, Ain; Karu, Veiko; Västrik, AireKolloquium Schacht, Strecke und Tunnel 2008 : 17. und 18. April 2008 : Freiberg/Sachsen2008 / p. 161-172 : ill