2010NF M60-517:2010 Reference sources - Calibration of surface contamination monitors - Alpha-, beta- and photon emitters.
1998NF M60-517-2:1998 Reference sources for the calibration of surface contamination monitors. Part 2 : electrons of energy less than 0,15 MeV and photons of energy less than 1,5 MeV.
1988NF M60-517:1988 Reference sources for the calibration of surface contamination monitors. Beta-emitters (maximum beta energy greater than 0,15 mev) and alpha-emitters.