Constancy testing of nuclear medicine instruments – Part 11: Radionuclide calibrators (IEC/TR 61948-4:2006, modified)
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 05/01/2009

Constancy testing of nuclear medicine instruments – Part 11: Radionuclide calibrators (IEC/TR 61948-4:2006, modified)
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 08/01/2016