1. CERN 1993. GEANT: Detector description and simulation tool, Application Software Group, CERN, Geneva.
2. A determination of the half-life of 137Cs;Gostely;Int. J. Appl. Radiat. Isot.,1991
3. ICRU 1979. Average energy required to produce an ion pair. ICRU Report 31, 28.
4. The international reference system for activity measurements of gamma-ray emitting nuclides;Rytz;Int. J. Appl. Radiat. Isot.,1983
5. Schrader, H. 1997. Activity measurements with ionization chambers. Monographie BIPM-4.