Hirota M, Nemoto K, Wada A, Igarashi Y, Aoyama M, Matsueda H, et al
. Spatial and temporal variations of atmospheric 85Kr observed during 1995-2001 in Japan: estimation of atmospheric 85Kr inventory in the Northern Hemisphere. J Radiat Res. 2004;45:405-13 pubmed
..The global atmospheric inventory of 85Kr in December 2001 was also estimated to be approximately 5 EBq by using observed data in Tsukuba...