Decay properties of neutron-deficient isotopes 256,257Db, 255Rf, 252,253Lr F.P. Heßberger, S. Hofmann, D. Ackermann, V. Ninov, M. Leino, G. Münzenberg, S. Saro, A. Lavrentev, A.G. Popeko, A.V. Yeremin and Ch. Stodel Eur. Phys. J. A, 12 1 (2001) 57-67 Published online: 15 September 2001 DOI: 10.1007/s100500170039