[NATURAL RADIOACTIVITY OF THE SOIL].
D011194:Potassium Isotopes; D011851:Radioactivity; D011874:Radiometry; D012987:Soil; D013910:Thorium; D014586:USSR; D014501:Uranium
D011194:Potassium Isotopes; D012987:Soil; D014501:Uranium; D013910:Thorium
POTASSIUM ISOTOPES; RADIOACTIVITY; RADIOMETRY; SOIL; THORIUM; URANIUM; USSR
ESTESTVENNAIA RADIOAKTIVNOST' POCHV.