Radionuclide concentration variations in residues from potential NORM industries in Estonia : the example of oil shale-fired power plantsVaasma, Taavi; Kiisk, Madis; Realo, Enn; Loosaar, Jüri; Tkaczyk, Alan HenryV. Terrestrial Radioisotopes in Environment : International Conference on Environmental Protection2016 / p. 30 http://dx.doi.org/10.18428/TREICEP-2016 Radionuclide concentration variations in the fuel and residues of oil shale-fired power plants : estimations of the radiological characteristics over a 2-year periodVaasma, Taavi; Loosaar, Jüri; Kiisk, Madis; Tkaczyk, Alan HenryJournal of environmental radioactivity2017 / p. 25-33 : ill https://doi.org/10.1016/j.jenvrad.2016.10.005