Sinchenko, V. “SPECTROMETRY OF RADIONUCLIDES Cs-137 AND Sr-90 IN SURFACE FRESH WATERS AND CONFORMITY OF THEIR ACTIVITY TO PERMISSIBLE LEVELS”. Ecological Safety and Balanced Use of Resources, no. 2(22), Feb. 2021, pp. 58-71, doi:10.31471/2415-3184-2020-2(22)-58-71.