Probing the Majorana mass scale of right-handed neutrinos in mSUGRA F. Deppisch, H. Päs, A. Redelbach, R. Rückl and Y. ShimizuEur. Phys. J. C, 28 3 (2003) 365-374DOI: https://doi.org/10.1140/epjc/s2003-01184-6