1. (a) K.H. Leiser, Radiochim. Acta 63 (1993) 5.
2. (b) E. Holm, Radiochim. Acta 63 (1993) 57.
3. (c) M. Kubota, Radiochim. Acta 63 (1993) 91.
4. See the special issue devoted to the chemistry of technetium and rhenium in: K. Yoshihara, T. Omori, eds., Topics Curr. Chem. 176 (1996).
5. (a) J.L. Pierre, P. Barret, Bull. Chem. Soc. Fr. (1983) 367.