Annotated record and Radium content of the detailed examination of manganese nodules from lakes and peripheral waters of Russia as well as the Pacific Ocean

At the date of publication the radioactivity of bottom sediments had only been published by a few authors. The radioactivity of selected characteristic ferro-manganese formations samples taken from different seas and lakes has been determined. This investigations covers nine seas and lakes of the U.S.S.R., and for comparison, two manganese concretions from the Pacific.