Primary activity measurements with 4πγ NaI(Tl) counting and Monte Carlo calculated efficiencies - Nedjadi, Youcef; Spring, Philippe; Bailat, Claude; Decombaz, Marc; Triscone, Gilles; Gostely, Jean-Jacques; Laedermann, Jean-Pascal; Bochud, François O. (Applied Radiation & Isotopes, 2007)