Microwave reflection properties of building materials in the working environmentKoppel, Tarmo; Haldre, Heldur56th International Riga Technical University Conference "Scientific Conference on Economics and Entrepreneurship SCEE'2015" : proceedings2015 / p. 148-150 : tab Minimising radiofrequency radiation exposure of smart phones and tablets - using an off-line reader instead of wireless browsing for mobile learningAhonen, Mikko; Koppel, Tarmo56th International Riga Technical University Conference "Scientific Conference on Economics and Entrepreneurship SCEE'2015" : proceedings2015 / p. 144-145 : tab Radioactivity of Estonian groundwater and technology for its removalLumiste, Liie; Munter, Rein; Sutt, Johannes; Kivimäe, Tiit; Eensalu, ToivoWater pollution XI2012 / p. 211-221 State-of-the-art technology for natural radioactivity removal in groundwater [Online resource]Goi, AnnaOpen access government2018 / phot https://www.openaccessgovernment.org/radioactivity-removal-groundwater/51906/ Влияние радиоактивности графитовой пыли на обслуживание парогенератораButin, N.B.; Bõlkin, B.K.; Hruljov, A.A.Теплофизические исследования парогенератора с гелиевым теплоносителем1986 / с. 66-74 Определение радиоактивности методом ионизацииPaomets, V.; Meitre, JohannesСборник научных трудов студентов. 31960 / с. 65-69 : илл https://www.ester.ee/record=b2181418*est https://digikogu.taltech.ee/et/Item/3c57b85a-ce7a-4beb-ab6a-4e0c682a1d0b